GB2505093A - Photoelectric converter and photoelectrochemical cell - Google Patents

Abstract

Provided is a photoelectric converter comprising a conductive substrate, a photosensitive layer formed from a semiconductor microparticle layer containing a pigment, a charge transfer layer, and a counter electrode, wherein the semiconductor microparticles of the photoelectric converter locally have two or more metals or metal compounds and the pigment is a compound represented by general formula (1): ï¼­ï½ ï¼ ï¼¬ï¼¬1ï¼ m1ï¼ ï¼¬ï¼¬2ï¼ m2ï¼ ï¼¸ï¼ m3ã »ï¼ ï¼£ï¼©ï¼ m4 (general formula (1)) (where Mz is a metal atom, LL1 is a specific bidentate or tridentate ligand, LL2 is a specific bidentate or tridentate ligand, X is a specific monodentate or bidentate ligand, CI is an ion that neutralizes the charge of the compound represented by general formula (1), m1 is an integer between 1 and 3, m2 is an integer between 0 and 2, m3 is an integer between 0 and 3, and m4 is an integer between 0 and 3).

Description

I

DESCRIPTION

TITLE OF fNVENTION: PHOTOELECTRIC CONVERSION ELEMENT AND

PITOTOELECTROCIIEMTCAL CELL

TECHNICAL FIELD

f000l} The present invention relates to a photoelectric conversion element and a photoelectrocheinical cell, which have high conversion efficiency and are excellent in durability.

BACKOROIND ART 0O02

Photoelectric conversion elements are used in various photosensors. copying machines, photoelectrochemical cells (for example, solar cells), and the like. These photoelectric conversion elements have adopted various systems to he put into use, such as elements utilizing metals, elements utilizing semiconductors, elements utilizing organic pigments or dyes, or combinations of these elements Among them, solar cells that make use of non-exhaustive solar energy do not necessitate fttels, and full-fledged practicalization of solar cells as an inexhaustible clean energy is being highly expected.

Among these, research and developmenl of silicon-based solar cells have long been in progress. Many countries also support policy-wise considerations, and thus dissemination ofsilicon-hascd solar cells is still in progress. However, silicon is an inorganic material, and has limitations per se in terms of throughput and molecular modification.

Under such circumstances,research is being vigorously carried out on dye-sensilized solar cells. Particularly. Graetzel et al. at lEcole Polytechnique de lUniversite de Lausanne in Switzerland have developed a dye-sensitized solar cell in which a dye formed from a ruthenium complex is fixed at the surface of a porous titanium oxide thin film, and have realized a conversion efficiency that is comparable to that of amorphous silicon. Thus, the dye-sensitized solar cells instantly attracted the attention of researchers all over the world.

Patent literature 1 describes a dye-sensitized photoelectric conversion element making use of semiconductor line particles sensitized by a ruthenium complex dye, to which the foregoing technology has been applied. Moreover, a photoelectric conversion clement using an inexpensive organic dye as a sensiti7cr has been reported.

Patent Literature 2 proposes a photosensitized solar cell in which sunlight is effectively absorbed by using a dye having a specific structure to improve photoelectric conversion efficiency.

Moreover, a photoelectric cell is proposed in which a dopant is incorporated into at least one of a core and a shell of multi-structure titanium oxide fine particles having the core being a central part and the shell being an outer shell part to improve photoelectric conversion efficiency (for example, refer to Patent Literature 3).

The present inventors produced photoelectric conversion elements using the dye and the semiconductor fine particles described in these Patent Literatures, and evaluated the resultant elements. As a result, it is found that the elements are insufficient in some cases in view of durability. The photoelectric conversion element is required to have high initial conversion efficiency and a small decrease in conversion efficiency even after use and he excellent in durability. Therefore, the photoelectric conversion elemenis described in these Patent Literatures are unsatisfactory.

CITATION LIST

Patent Literatures {O005 Patent Literature I: U.S. Patent No. 5,463,057 Patent Literature 2: JP-A-2009-200028 (iF-A" means unexamined published Japanese patent application) Patent Literature 3: JP-A-2004-10403

DISCLOSURE OF INVENTION

TECHNICAL PROBLEM

{ 0006} The present invention provides a photoelectrochemical cell and a photoelectrocliemical cell which have high conversion efficiency and are excellent in durability.

SOLUTION TO PROBLEM

t0007} The present inventors diligently conducted research on photoelectric conversion efficiency and durability by producing photoelectric conversion elements using various semiconductor fine particles and dyes. As a result, the present inventors found that durability cannot be significantly improved by simply niixing different kinds of semiconductor fine particles, and that a simple use ot as semiconductor fine particles, those prepared by coating tin oxide with aluminum oxide or magnesium oxide is difficult to improve durability.

Thus, the present inventors diligently conducted research on semiconductor fine particles and a dye. As a result, the present inventors found that a photoelectric conversion element and a photoelectrochemical cell, in which semiconductor fine particles have two or more kinds of metals or metallic compounds, and a metal complex dye having a specific suhstitucnt in a ligand is used, arc excellent not only in initial phoLoelectric conversion efficiency but also in durability.

The present invention was made based on these findings.

(0008} The present invention provides the following means: <1> A photoelectric conversion element, comprising: an electrically conductive support; a photoconductor layer having semiconductor fine particles containing a dye: a charge transfer layer; and a counter electrode; wherein the semiconductor fine particles locally have two or more kinds of metals or metallic compounds, and wherein the dye is a compound represented by Formula (I): MZU;L')mi(L11m2(X)rn3(CT)m4 Formula (1) wherein Mz represents a metal alorn; LL' is a bidentale ligand represenled by Formula (2): LL2 is a hidentate or terdentate ligand represented by Formula (3); X represents a monodentate or hidentate ligand selected from the group consisting of an acyloxy group, an acylthio group, a thicacyloxy group, a thioacylthio group, an acylaminooxy gyoup, a thiocarbamate group, a dithiocarbamate group, a thioearbonate group, a dithioearhonate group, a trithiocarhonate group, an acyl group, a thiocyanate group, an isothiocyanate group, a cyanate group, an isocyanate group, a cyano group, an alkylthio group, an arylthio group, an alkoxy group and an aryloxy group, or a monodentate or bidentate ligand selected from the group consisting of a halogen atom, carbonyl, a diallcylketone, a 1,3-diketone, a earbonamide, a thiocarhonamide and a thiourea; C! represents a counter ion for neutralizing a charge of the compound represented by Formula (U; ml represents an integer of ito 3; when ml is an integer of 2 or more, LL l's may be the same or different from each other; m2 represents an integer of 0 to 2; when m2 is an integer of 2, LL2's may he the same or different from each other; m3 represenis an integer of 0 to 3; when m3 is an integer of 2 or more, X's may be the same or different from each other; m4 represents an integer of 0 to 3; when m4 is an integer of 2 or more, Cl's may he the same or different from each other; (0009} __9L21-R106) (R1O5a/ Formula (2) . )i (R)b2 (0010} wherein R10' and RIO2 each independently represent a heterocyclic group. a carhoxyl group, a sulfonic acid group, a hydroxyl group, a hydroxamic acid group, a phosphoryl group or a phosphonyl group; R'°3 and R'°4 each independently represent a substituent; R'° and R'°' each independently represent a group composed of at least one kind of group selecled from the group consisting of an alkyl group, an aryl group and a heterocyclic group; and each independently represent a conjugated chain composed of an ethenylene group andIor ethynylene group; a 1 and a2 each independently represent an integer of 0 to 3; when a 1 is an integer of2 or more, R'°''s maybe the same or different from each other; when a2 is an integer of 2 or more, R10' s may be the same or different from each other; hi and b2 each independently represent an integer of 0 to 3; when hi is an integer of 2 or more, may be the same or different from each other, or Rm3s may be bonded to each other to form a mg; when b2 is an integer of 2 or more, R'°4's may be the same or different from each other, or R'°4's may be bonded to each other to form a ring; when hi and h2 each are an integer of I or more, R'°3 and R'°4 maybe bonded to each other to form a ring; dl and d2 each independently represent an integer of 0 to 5; d3 represents 0 or 1; and {00l l} Za. (7b* ?Zc.

NrN)) Formula (3) (00l2} wherein Za, Zb and Zc each independently represent a group of non-metallic atoms for forming a 5-or 6-membered ring; and c represents 0 or I. <2> The photoelectric conversion element described in the above item <1>, wherein the two or more kinds of metals or metallic compounds in the semiconduclor fine particles are a metal atom, metal chalcogenide. metal carbonate or metal nitrate.

<3> the photoelectric conversion eiement described in the above item <2>, wherein the metal atom is at least one kind of atom selected from the group consisting of Ti, Sn, Au, Ag. Cu, Al. Zr, Nb, V and Ta.

cz4> The photoelectric conversion element described in the above item <2> or <3>, wherein the metal chalcogenide is cadmium sulfide, cadmium selenide or a metal oxide of at least one kind of metal selected from the group consisting of Ti, Sn. Zn. Mg, Al, W, Zr, Hf, Sr, In, Ce, Y, La, V and Ta.

<5> The photoelectric conversion element described in any one of the above items <2> to <4>, wherein the metal carbonate is at least one kind of metal carbonate selected from the group consisting of calcium carbonate, potassium carbonate and barium carbonate.

<6.> Ihe photoelectric conversion element described in any one of the above items <2> to -c3>, wherein the metal nitrate is lanthanum nitrate.

<7> The photoelectric conversion element described in any one of the above items <2> to <6>. wherein the semiconductor fine particles have the metal atom, the metal chalcogenide, the metal carbonate and/or the metal nitrate, according to a core-shell structure.

<5> The photoelectric conversion clement described in the above item <7>, wherein the semiconductor fine particles have the metal chaicogenide as a core part, and have the metal chalcogenide or the metal carbonate as a shell part.

<9> The photoelectric conversion element described in the above item <8>, wherein the semiconductor fine particles have metal chalcogenide selected from the group consisting of titanium oxide and tin oxide as the core part, and have metal chalcogenide or metal carbonate selected from the group consisting of aluminum oxide, magnesium oxide, calciuni carbonate, titanium oxide, and titanium oxidc/niagnesi tm oxide as the shell part <:10> The photoelectric conversion element described in any one of the above items <I> to <6>, wherein the semiconductor tine particles have the two or more kinds of metal atoms by doping a mcml atom.

<:11> The photoelectric conversion element described in the above item <10>, wherein the semiconductor fine particles are obtainable by doping a metal atom into metat chalcogenide.

<12> The photoelectric conversion element described in the above item <11>, wherein the semiconductor fine particles are semiconductor fine particles obtainable by doping at least one kind of metal atom selected from the group consisting of Nb, \T and Ta into metal chaleogenide selected from the group consisting of titanium oxide and tin oxide.

<13> The photoelectric conversion element described in any one of the above items <1> to <12>, wherein a particle diameter of the semiconductor fine particles is ito 1,000 tim.

<14> The photoelectric conversion element described in any one of the above items <1> to <13>, wherein the semiconductor fine particles contain an additive composed of an electrically conductive material.

<15> the photoelectric conversion clement described in the above item <14>, wherein the electrically conductive material is grapheme.

<16> The photoelectric conversion element described in any one of the above items <1> to <15>, wherein, in Fomiula (1), Mz is Ru, ml is 1, m2 is 1, X is an isothiocyanate group, and m3 is 2.

<17> The photoelectric conversion clement described in any one of the above items <1> to <16>, wherein, in Fonnula (1), LL' is represented by any one of Formulas (4-1), (4-2) and (4-3): (R125)d4 (R126)d5 \ / p P

N I R d3

I2/ Formula (4 -1) (R1 °3)bl @b04 (R1)ja (R'26)d5 \\ OC=CH

N

US Formula (4 -2) lOB (R)b3 R127_-_ftC=CH ( HC=H_(jj 128' C d3 Formula (4 3) (R1' N )11 (R )b2 wherein R'°' to RI(M, ai, a2, hi, b2 and d3 have the same meaning as those in Formula (2), respectively; R'' represents an acidic group; a3 represents an integer of 0 to 3: R1°5 represents a substituent; h3 represents an integer ofO to 3; R'21 to R'24 each independently represent a hydrogen atom, an alkyl group, an alkenyl group or an aiyl group; R'2, R'26, R' and R'25 each independently represent a substittient; and d4 and d5 each independently represent an integer of 0 to 4.

-C 18> A photoclcctrochcmical ccli, comprising thc pliotoclcctric conversion cicmcnt described in any one of the above items -ci> to <17>

ADVANTAGEOUS EFFECTS OF INVENTION

(00l5} According to the present invention, it is possible In provide a pholoelectric is conversion element and a photoelectrochemieal cell which exhibit high conversion efficiency and excellent durability.

{ 0016 Other and further features and advantages of the invention will appear more fully from the following description, appropriately referring to the accompanying drawing.

BRWF DESCPTION OF THE DRAWING {OOl7

fFIG l} Fig. I is a cross-sectional view schematically showing an exemplary embodiment of the photoe1eduic conversion element according to the present invention. 1 0

MODE FOR CARRYING OU1'[HE INVENtION

{00I8} The present inventors diligently conducted research, and as a result, found that a photoelectric conversion element and a photoelectrochemical cell comprising an elecuically conductive support, a photoconductor layer having a semiconductor fine particle layer containing a dye of a specific compound, a charge transfer layer and a counter electrode, in which the semiconductor fine particles locally have two or more kinds of metals or metallic compounds, have high conversion efficiency and are excellent in durability. The present invention is achieved based on these findings.

f0019} A prefelTed exemplary embodiment of the photoelectric conversion element of the present invention will be explained with reference to the schematically cross-sectional view shown in Fig. 1.

(0020} As shown in Fig. 1, a photoelectric conversion element 10 contains an electrically conductive support 1; and a photoconductor layer 2, a charge transfer layer 3 and a counter clcctrodc 4, all provided on the electrically conductive support I in this order. The electrically condLLctive support 1 and the photoconductor layer 2 constilute a light-receiving electrode 5.

the photoeonductor layer 2 has semiconductor fine particles 22 and a sensitizing dye (hereinafter, also simply referred to as "dye") 21. The sensitizing dye 21 is at least partially adsorbed on the semiconductor fine particles 22 (the sensitizing dye 21 is in an adsorption equilibrium state, and may partially exist in the charge transfer layer 3.). The charge transfer layer 3 functions, for example, as a hole-transporting layer for transporting positive holes (holes). The electrically conductive support I having a photoconductor layer 2 provided thereon functions as a working electrode in the photoelectric conversion element 10. This photoelectric conversion clcmcnt 10 can bc opcratcd as a photoclcctrochcmical ccli 100 by making thc photoelectric conversion element 10 usable in a cell application where the cell is made to work with an external circuit 6.

{0021} The light-receiving elcctrodc 5 is an electrode comprising an electrically conductive support 1; and aphotoconductor layer 2 (photosensitive layer or semiconductor film) coated on the electrically conductive support 1, the layer containing semiconductor fine particles 22 to which a sensitizing dye 21 has been adsorbed. A light incident to the photoconductor layer 2 (semiconductor film) excites thc dyc. Thc cxcitcd dyc has clcctrons with high energy, and thcsc electrons arc transported from the sensitizing dye 21 to the conduction band of the semiconductor fine particles 22 and further reach the electrically conductive support I by diffusion. At this time, the molecules of the sensitizing dye 21 are in an oxide form. In the photoclectrochemical cdl 100. thc clectrons on thc electrode rcturn to thc oxide of thc dye while working in the exiemal circuit 6, while the light-receiving electrode 5 works as a negative electrode of this cell.

(0022} Thc photoconductor layer 2 comprises a porous semiconductor layer constituled of a layer of the semiconductor fine particles 22 on which the dye described later is adsorbed. This dye may be partially dissociated in an electrolyte. The photoconductor laycr 2 is designcd for any purposc. and may form a multilayer struclure.

As described above, the photoconductor layer 2 contains the semiconductor fine particles 22 on which a specific dye is adsorbed, and thus has a high light-receiving sensitivity. When it is used for the photoelectrochemical cell 100, a high photoelectric conversion efficiency and higher durability can be obtained.

{ 0024 (A) Dye In the photoconduclor layer 2, a porous semiconductor layer is sensitiLed with at least one kind of dye 21 represented by Fonnula (1).

Mz(LL1)nii(LL)rn2(X)m3CI Formula (1) {0025} (A 1) Metal atom Mz Mz represents a metal atom. Mz is preferably a metal that is capable of tetracoordination or hexacoordination; more preferably Ru, Fe, Os, Cu. W, Cr, Mo, Ni, Pd. Pt, Co, Ir, Rh, Re, Mn or Zn; particularly preferably Ru. Os, Zn or Cu; and most preferably Ru.

(A2) Ligand LL' The ligand LL' is a bidentate ligand represented by Formula (21).

ml that represents the number of ligands represented by TI.1 is an integer of 1 to 3. When ml is an integer of 2 or more, LL' s may he the same or different from each other. ml is preferably I. RU_Lh1 L]R106) (R105at,/ Formula (2) 3 \ 104 \ Jbl (R)b2 In Formula (2), R'°' and R'°2 each independently represent any one of a heterocyclic group, a carboxyl group. a sulfonie acid group, a hydroxyl group, a hydroxamic group (preferably having ito 20 carbon atoms; for example, -CONHOH, -CONCI-l3OH. and the like), a phosphoryl group (for example, -OP(O)( H)2, and the like) and a phosphonyl group (for example, -P(O)(H)2, and the like). The heterocyclic group may be unsubstituted or substituted with a substituent described below. R'°' and R'°2 each are preferably a carhoxyl group or a phosphonyl group, and more preferably a carboxyl group. R'°' and R'°2 may be substituled at any sue of the pyridine-ring-forming carbon atoms.

f0029} al and a2 each independently represent an integer of 0 to 3. When al is an integer of 2 or more, R'°''s may be the same or different from each other. When a2 is an integer of 2 or more, R10' s may be the same or different from each other. al is preferably 0 or 1, and a2 is preferably an integer of 0 to 2. [he total of al and a2 is preferably an integer of 0 to 2. 0O30

In Formula (2), R'°3 and R'4 each independently represent a substituent.

Preferred examples thereof include an alkyl group (preferably an alkyl group having 1 to 20 carbon atoms, e.g. methyl, ethyl, isopropyl, t-hutyl, pentyl, hcptyl, 1-ethylpentyl, benzyl, 2-ethoxyethyl, or 1-carboxymethyl), an alkenyl group (preferably an alkenyl group having 2 to 20 carbon atoms, e.g. vinyl, allyl, or oleyl), an alkynyl group (preferably an alkynyl group having 2 to 20 carbon atoms, e.g. ethynyl, butadiynyl, or phenylethynyl) a cycloalkyl group (preferably a cycloalkyl group having 3 to 20 carbon atoms, e.g. cyclopropyl, cyclopenlyl, cyclohexyl, or 4-methylcyclohexyl). an aryl group (preferably an aryl group having 6 to 26 carbon atoms, e.g. phenyl, l-naphthyl, 4-mcthoxyphenyl, 2-chlorophcnyl, or 3-mcthylphcnyl), a hctcrocyclic group (prcfcrahly a heterocyclic group having 2 to 20 carbon atoms, eg 2-pyridyl, 4-pyridyl, 2-irnidazolyl, 2-benzirnidazolyl, 2-thiazolyl, or 2-oxazolyl), an alkoxy group (preferably an alkoxy group having I to 20 carbon atoms, e.g. metboxy, ethoxy, isopropyloxy, or ben7yloxy), an aryloxy group (preferably an aryloxy group having 6 to 26 carbon atoms, e.g. phenoxy,l-naphthyloxy, 3-methyiphenoxy, or 4-methoxyphenoxy), an alkoxycarbonyl group (preferably an alkoxycarbonyl group having 2 to 20 carbon atoms, e.g. ethoxycarbonyl, or 2-ethylhexyloxycarbonyl), an amino group (preferably an amino group having 0 to 20 carbon atoms, e.g. amino. N,N-dimethylamino, N,N-diethylamino, N-ethylamino, or anilino). a sulfonamide group (preferably a sulfonamide group having 0 to 20 carbon atoms, e.g. N,N-dimethylsulfonamide, or N-pheny1sulfonamide, an acyloxy group (preferably an acyloxy group having 1 to 20 carbon atoms. e.g. acetyloxy, or henzoyloxy), a carhanioyl group (preferably a carhamoyl group having 1 to 20 carbon atoms, e.g. N,N-dimethylcarbamoyl, or N-phenylcarbarnoyl), an acylamino group (preferably an acylamino group having 1 to 20 carbon atoms, e.g. acetylamino, or bcn7oylamino), a cyano group, and a halogen atom (e.g a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom). Among these, an alkyl group, an alkenyl group, an aryl group, a heterocyclic group, an alkoxy group, an aryloxv group, an alkoxycarbonyl group, an amino groupS, an acylamino group, a cyano group and a halogen atom are more preferable; and an alkyl group, an ailcenyl group, a heterocyclic group, an alkoxy group, an alkoxycarbonyl group, an aniino group, all acylamino group and a cyano group are particularly preferable.

t003 i} hi and h2 each independently represent an integer of 0 to 3, preferably an integer of 0 to 2. When hi is an integer of 2 or more, R'°3's maybe the same or different from each other, or R"13's may be bonded with each other to form a ring.

When h2 is an integer of 2 or more, R'°4's maybe the same or different from each other, or R104's may be bonded with each other to form a ring. When hi and h2 each are an integer of I or more, R'°3 and R'°4 may he bonded with each other to form a ring. The ring 10 be fomied is not particularly limiled. PrefelTed examples of the ring include a benzene ring, a pyridine ring, a thiophene ring, a pyrrole rin2, a cyclohexane ring, and a cyclopcntanc ring.

(0032} In Formula (2), R105 and R16 each independently represent a group composed of at least one icind of group selected from the group consisting of an alicyl group, an aryl group and a hcterocyclic group. R10 and R106 each independently are preferably an aromatic group (preferably an aromatic group having 6 to 30 carbon atoms, for example, phenyl, a substituted phenyl group, naphthyl, or a substituted naphthyl group), or a heterocyclic group (preferably a heterocyclic group having I to 30 carbon atoms, for example, a 2-thienyl group, a 2-pynolyl group, a 2-imidazolyl group, a 1-imidazolyl group, a 4-pyridyl group, or a 3-indolyl group), more preferably a heterocyclic group having 1 to 3 electron donative groups, and further preferably a thienyl group. The electron donative group is preferably an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, all alkoxy group, an aryloxy group, an amino group, an acylamino group (preferable examples of each of the above-described groups are the same as and R'°2 in Formula (2)) or a hydroxyl group; more preferably an alkyl group, an alkoxy group, an amino group or a hydroxyl group; and particularly preferably an alkyl group.

R'°5 and R'°6 may he the same or different from each other. however, it is preferable thatR'°5 and R'°6 are the same.

{0033} In Formula (2), L' and L7 each independently represent a conjugated chain composed of an ethenylene group and/or ethynylene group. When the ethenylene group has a substituent, examples of the substituent include those represented as specific examples of the substituent of R'°3 and K'°4. in the case where the ethenylene group has a substituent, the substituent is preferably an alkyl group, and more preferably a methyl group. Preferably ii and L2 each independently stand for a conjugated chain having 2 to 6 carbon atoms, more preferably an ethenylene group, a butadienyenc group, an ethynylene group, a butadiynylene group, a methylethenylene group, or a dimethylethenylene group; especially preferably an ethenylene group, or a hutadienylcne group; and most preferably an ethenylcne group. L' and L2 may he thc same or different from each other. However, it is preferable that L' and L2 are Ihe same.

Herein, when the conjugated chain contains a carbon-carbon double bond, each carbon-carbon double bond may he a trans form or a cis form, or a mixturc thereof.

(0034} dl and d2 each independenQy represent an integer of 0 to 5. When dl and d2 are 0, R'° and REOo are directly bonded to the benzene ring, respectively. When dl and d2 are an integer of I or more. R°5 and R1° are bonded to the henzene ring via L' or L2, respectively. dl and d2 each are preferably 0 or 1.

{ 00351 d3 is 0 or 1. When d3 isO, a2 is preferably 1 or 2. When d3 is 1, a2 is preferably 0 or 1.

In the case where the ligand LL1 contains an alkyl group, an alkenyl group or the like, these groups may be. linear or branched, and may be substituted or unsubstituteci. Likewise, in the case where the ligand LL' contains an aromatic group, such as an aryl group, a heterocyclic group or the like, these groups may be a single ring or a condensed ring, and may be substituted or unsubstituted. Examples of the substituent include those represented as specific examples of the substituent of R'°3 and {OO37 Ihe ligand II' in Forrnula(l) is preferably represented by Formula (4-1), (4-2) or (4-3). (R)d4

(R120)d5 \ / / P HG R123

N I

= 124 1 Formula (4 -1) R d3 (R103)b1 N N l043 (R126)d5 R123 N) p122 124 / Formula (4 2) R d3 10l)i NQ (R107) R121_)G=CH ( H H /sTh 128\ ce_R)d3 Formula (4 3) s I0I (S1 03) In Formulae (4-1) to (4-3), R'°' to R'°4. al. a2, bI, b2 and d3 have the same meaning as those in Formula (2), respectively, and preferable ranges thereof are also the same.

In Formula (4-2), K'°7 represents an acidic group. K'° is preferably a carboxyl group, a sulfonic acid group, a hydroxyl group., a hydroxamic group, a phosphoryl group or a phosphonyl group; more preferably a carhoxyl group or a phosphoryl group; and further preferably a carboxyl group.

In Formula (4-2), a3 rcprcscnts an intcgcr of 0 to 3, prcfcrably an intcgcr of 0 to 2. When d3 is 0, a3 is preferably I or 2. When d3 is 1, a3 is preferably 0 or 1. When a3 is an integer of 2 or more, R1°"s may he the same or different from each other.

{0042} In Formula (4-2), OS rcprcscnts a substitucnt; prcferably an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, an alkoxy group, an aryloxy group, an amino group, or an acylamino group (preferable examples of each of the above-described groups are the same as R'°3 and K"14 in Formula (2)): more preferably an alkyl group, an alkoxy group, an amino group or an acylamino group.

In Formula (4-2), b3 represents an integer of 0 to 3, preferably an integer of 0 to 2. When b3 is an integer of 2 or more, K1 s may be the same or different from each other.

f0044} In Formulas (4-1) and (4-2), K12' o K'24 each independently represent a hydrogen atom, an alkyl group, an ailcenyl group, or an aiyl group (preferable examples of the ahovc groups arc the sarnc as R'°3 and R'°4 in Formula (2)). R'2' to R' each arc prcfcrably an alkyl group or an aryl group; and rnorc prcfcrably an alkyl group. Whcn K'2' to K'24 are an alkyl group, the alkyl group may additionally have a substituent. As for the substituent, an alkoxy group, a cyano group an alkoxycai'bonyl group, or a carhonamidc group is prcfcrahlc, and an alkoxy group is cspccially prcfcrable.

K'2' and K'22, and K'23 and K'24 are each bonded with each other to form a ring.

Preferable examples of the ring to be formed include a pynolidine ring, a piperidine ring, a piperazine ring, and a morpholine ring.

In Formulas (4-1) to (4-3), R'25, R', R'27 and R' each independently represent a substituent; preferably an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, an alkoxy group, an aryloxy group, an amino group, an acylamino group (preferable examples of each of the above-described groups are the same as and R1M in Formula (2)) or a hydroxyl group; more preferably an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, an amino group or an acylamino group; and particularly preferably an alkyl group or an alkynyl group.

(0046} In Formulas (4-1) and (4-2), d4 and dS each independently represent an integer * 121 122 ofoto4. Whend4tslormore,R maybebondedwithR and/orR toforma ring. The formed ring is preferably a piperidine ring or a pyrrolidine ring. When d4 is 2 or more, R'25's may be the same or different from each other, or may be bonded with each other to form a ring. When d5 is I or more, R'26 may be bonded with Rim and/or R'24 to form a ring. The formed ring is preferably a piperidine ring or a pyrrolidine ring.

When dS is 2 or more, Rths may be the same or different from each other, or may be bonded with each other to form a ring.

(0047} (A3) Ligand LL2 The ligand LI? is a bidentate or tridentate ligand represented by Formula (3).

The ligand LL2 is preferably a bidentate ligand.

m2 that represents the number of ligands represented by LL2 is an integer of 0 to 2, preferably 0 or 1; more preferably 1. When m2 is an integer of 2, the ligands LL2's may be the same or different from each other.

In the present invention, the ligand LL2 preferably has an acidic group, such as a earboxyl group, a sulfonic acid group, a hydroxyl group, a hydroxamie group, a phosphoryl group and a phosphonyl group.

(0048) f Zb It Zc. * S

* : *, \** Formula (3) In Formula (3), Za, Zh and Zc each independently represent a group of non-metallic atoms for forming a 5-or 6-menibered ring. The formed 5-01 6-membered ring may he substituted or unsubstituted, and may he a single ring or a condensed ring Examples of the subsli[uenl include the substilueni W described below. {OO50

Each of Za, Zb and Ze is preferably a 5-membered ring or the 6-membered ring composed of a carbon atom, a nitrogen atom, an oxygen atom, a sulfur atom and/or a phosphor atom. The 5-meinhered ring and the 6-membered ring may have a hydrogen atom, a halogen atom or the like. ia, lb and i.e each are preferably an aromatic ring group. in the case of the 5-membered ring, an imidazole ring, an oxazole ring, a thiazole ring, or a triazole ring is preferably formed. In the case of the 6-membered ring, a pyridine ring, a pyrimidine ring, a pyridazine ring, or a pyrazine ring is preferably formed. Among these rings, an imidazole ring and a pyridine ring are more preferable.

{0051} In Formula (3), c represents 0 or 1.

t0052} higand LL2 is preferably represented by any one of Fonnula (5-1) to Formula (5-8); more preferably represented by Formula (5-1), Formula (5-2), Formula (5-4) or Formula (5-6); especially preferably represented by Formula (5-1) or Formula (5-2); and most preferably represented by Formula (5-1).

(R155es (Rl63)ei3 "-N N (R151)i Formula (5-5) (R15Y)__..*KO R16° Rlcc /

N

152 Formula (5-1) ( Q)e2 N N Formula ( 5 6) (R1)elO \__ 60)is Formula (R' )e3 N (R161)eu Formula (5 7) I53 (65el6 Formula ) eB F 154) (R' / e4)e12 1Jo R171 Formula ( 5-4) Formula (5 -8) Herein, R' to R'66 in Formulas (5-1) to (5-8) are represented to be substituted on a single ring for convenience of illustration hut may he on the ring or may he S subsli[uted on a ring different from one illustrated.

In Formulas (5-1) to (5-8), R1' to R1 each independently represent an acidic group. to R'5 each are, for example, a carboxyl group, a sulfonic acid group, a hydroxyl group, a hydroxarnie group (preferably having 1 to 20 carbon aloms for example, -CONHOH, -CONCI-130H. and the like), a phosphoryl group (for example, -OP(OH)2. and the like) or a phosphonyl group (for example, -P(O)(H)2. and the like); preferably a earboxyl group, a phosphoryl group or a phosphonyl group; more preferably a earboxyl group or a phosphonyl group; and most preferably a earboxyl group.

{0056} In Formulae (5-1) to (5-8), RID9 to R166 each independently represent a substituent. R'59 to R'66 each are preferably an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, a heterocyclie group, an alkoxy group, an aryloxy group, an alkoxycarhonyl group, an amino group, an acyl group, a sullonamide group, an acyloxy group, a carbamoyl group, an acylamino group, a cyano group, or a halogen atom (preferable examples of each of the above-described groups are the same as and R'°4 in Formula (2)); more preferably an alkyl groupS, an alkenyl group, an aryl group, a heterocyclic group, all alkoxy group, an alkoxycarhonyl group, an amino group, an acylamino group, or a halogen atom; and especially preferably an ailcyl group, an alkenyl group, an alkoxy group, an alkoxycarbonyl group, an amino group, or an acylamino group.

In Formulae (5-I) to (5-8), R16' to R17' each independently represent a hydrogen atom, an aliphatic group, an aromatic group, or a heterocyclic group bonding to the ring via a carbon atom. Each of R'67 to R'7' represents preferably an aliphatic group or an aromatic group, and more preferably an aliphatic group having a carhoxyl group.

In Formulae (5-I) to (5-8), each ofR15' to R'66 may bind to any site of the rings.

f0059} In Formulae (5-1) to (5-6), ci o e6 each independendy represeni an integer of o to 4, preferably an integer of 1 to 2. e7 and e8 each independently represent an integer of 0 to 4, preferably an integer ofO to 3, and more preferable an integer of I to 3.

e9 to ci 2 and ci 5 each independently represent an integer of 0 to 6. ci 3. ci 4 and e 16 each independently represent an inieger of 0 to 4. e9 in e16 each are pre!èrably an integer ofO to 3.

(0060} When each ofel to e8 is 2 or more, each of RIDI s lo RlDSs is the same or different from each other, or may be bonded with each other to form a ring. When each of e9 to el6 is 2 or more, each of RlD9s to R''s is the same or different from each other, or may he bonded with each other to form a ring.

When the ligand LL2 contains an alkyl group, an alkenyl group or the like, these groups may be linear or branched, and may be substituted or unsubstituted.

Meanwhile, when the ligand LL2 contains an aromatic group, such as an aryl group, a heterocyclic group or the like, these groups may be a single ring or a condensed ring, and may be substituted or unsubstituted.

f0062} (A4) Ligand X In Formula (1), the ligand X represents a monodentate or hidentate ligand described below. m3 that represents the number of ligands represented by X represents an integer of 0 to 3. in3 is preferably an integer of 0 to 2, more preferably 1 or 2.

When the ligand X is a monodentate ligand. m3 is preferably 2. When the ligand X is a bidentate ligand, m3 is preferably 1. When m3 is an integer of 2 or more, X's may be the same or different from each other, or X's may be bonded to each other.

{0063} The ligand X represents a monodentate or hidentate ligand selected from the group consisting of an acyloxy group (preferably an acyloxy group having 1 to 20 carbon atoms, for example, acetyloxy, benzoyloxy, salicylic acid, glycyloxy, N.N-dimethyiglycyloxy. oxalylene (-OC( )C(O)O-). and the like), an acylthio group (preferably an aeylthio group having Ito 20 carbon atoms, for example, aeetylthio, benzoylthio, and the like), a Uioacyloxy group (preferably a Ehioaeyloxy group having 1 to 20 carbon atoms, for example, thioacetyloxy (CH3C( )O-) and the 111cc), a thioacylthio group (preferably a thioacylthio group having I to 20 carbon atoms, for example, thioacetvlthio (CFbC(S)S-). thiobenzoylthio (PhC(S)S-) and the like), an acylaminooxy group (preferably an acylarninooxy group having 1 to 20 carbon atoms, for example, N-niethylbenzoyl arninooxy (P1iC(( )N(CH3)O-), aeetylaminooxy (CH3C(O)NT-1O-) and the like), a thiocarharnate group (preferably a thioearhamate group having Ito 20 carbon atoms, for example, N,N-diethylthioearbarnale and the like), a dithiocarbamate group (preferably a dithiocarbamate group having I to 20 carbon atoms, for example, N-phenydithio carbamate, N,N-diniethyldithioearbamate, N,N-diethyldithioearbamate, N,N-dihenzyldithiocarbamate and the like), a thiocarhonate group (preferably a thiocarhonate group having to 20 carbon atoms, for example, ethylthiocarbonate and the like), a dithiocarbonate group (preferably a dithiocarhonate group having I to 20 carbon atoms, for example, ethyldithiocarhonate (C2TI5OC(S)S-) and the like), a trithiocarhonate group (preferably a trithiocarhonate group having Ito 20 carbon atoms, for example, ethyltrithiocarbonate (C2ThSC(S)S-) and the like), an acyl group (preferably an acyl group having 1 to 20 carbon atoms, for example, acetyl, hen7oyl and the like), a thioeyanate group, an isothiocyanate group a cyanate group. an isocyanate group, a cyano group, an alkylthio group (preferably an alkylthio group having 1 to 20 carbon atoms, for example, rnethanethio, ethylenedithio, and the like), an aiylthio group (preferably an arylthio group having 6 to 20 carbon atoms, for example, benzenethio, l,2-phcnylenedithio and the like), an alkoxy group (preferably an alkoxy group having I to 20 carbon atoms, for example. methoxy and the like) and an aryloxy group (preferably an aryloxy group having 6 to 20 carbon atoms, for example, phenoxy, quinoline-8-hydroxyl and the like), or a monodentate or bidentate ligand selected from the group consisting of a halogen atom (preferably a chlorine atom, a bromine atom, an iodine atom and the like). carhonyl (---CO); a dialicylketone (preferably a dialkylketone having 3 to 20 carbon atoms, for example, acetone ((H1)CO-") and the like), a 1.3-diketone (preferably a 1,3-diketone having 3 to 20 carbon atoms, for example, acetvlacetone (CT-J3C(&--)Cl-T=C(-)CT-T3), atrifluoro acetylacetone dipivaloylmethane (-C4H9C(O--)CH=C(O-)1-C4-I9), dibenzoylmethane (PhC(O--)CH=C(O-)Ph), 3-chloroacetylaeetone (CM C(O---)CC1=C(O-)C1-13) and the like), a carhonamide (preferably a carhonarnidc group having I to 20 carbon atoms, fbr example, CH1N=C(CH3)O-. -OC(NH)-C(NH)O-and the like), a thiocarbonamide (preferably a thiocarbonamide group having 110 20 carbon aloms, for example, CH5N=C(CH3)S-and the like), and a thiourea (preferably a thiourea having I to 20 carbon atoms, for example, (Nl-l(---)=C(S-)NH2, CI-I3NH(---)=C(S-)NHCH3, (CH3)2N-C(S---)N (CH1) and the like).

Nole that"" indicates a coordinale bond.

{0064J the ligand Xis preferably a ligand selected from the group consisting of an acyloxy group, a thioaeylthio group, an aeylaminooxy group, a dithioearbamate group, a dithiocarbonate group, a trithiocarbonate group, a thiocyanate group, an isothiocyanate group, a cyanate group, an isocyanate group, a cyano group, an alkylthio group, an arylthio group, an alkoxy group and an aryloxy group, or a ligand selected from the group consisting of a halogen atom, carhonyl, a I,3-diketone and a thiourea; more preferably a monodentate or bidentate ligand selected from the group consisting of an acyloxy group, an acylanilnooxy group, a dithiocarbamate group, a thiocyanate group, an isothiocyanate group, a cyanate group, an isocyanate group, a cyano group and an arylthio group, or a monodentate or bidentate ligand selected from the group consisting ofahalogen atom, a 1,3-diketone and a thiourea; especially preferably a ligand selected from the group consisting of a dithiocarbamate group, a thiocyanate group, an isothiocyanate group, a cyanate group and an isocyanate group, or a ligand selected from the group consisting of a halogen atom and a I,3-diketone; most preferably a monodentate or bidentate ligand selected from the group consisting of a dithiocarbamate group, a thiocyanate group and an isothiocyanate group, or a ligand composed of a 1,3-diketone; and most preferably an isothiocyanate group, Note that in the case where the ligand X contains an alkyl group, an alkenyl group, an alkynyl group, an alkylene group or the like, these groups may be linear or branched, and may be substituted or unsubstituted. In the case where the ligand X contains an aromatic group, such as an aryl group, a heterocyclic group, a cycloalkyl group or the like, these groups may be substituted or unsubstituted, and may be a single ring or a condensed ring.

In the case where the ligand X is a bidentate ligand, the ligand X is preferably a ligand selected from the group consisting of an acyloxy group, an acylthio group, a thioacyloxy group, a thioacylthio group, an acylaminooxy group, a thiocarbamate group, a dithiocarbamate group, a thiocarbonate group, a dithiocarbonate group, a trithiocarbonate group, an acyl group, an alkylthio group, an arylthio group, an alkoxy group and an aryloxy group, or a ligand selected from the group consisting of a 1,3-diketone, a carbonamide group, a thiocarbonamide group and a thiourea. In the case where the ligand X is a monodentate ligand, the ligand X is preferably a ligand selected from the group consisting of a thiocyanate group, an isothiocyanate group, a cyanate group, an isocyanate group, a cyano group, an alkylthio group and an arylthio group, or a ligand selected from the group consisting of a halogen atom, carhonyl, a dialkylketone and a thiourea.

{ 0066 (AS) Counter ion Cl CI in Formula (1) represents a counter ion in the case where the counter ion is necessary to neutralize a charge. Uenerally, whether the dye is cationic or anionic, or has a net ionic charge depends on the metal, the ligand and thc suhstituent in the dye t0067} In the case where the substituent has a dissociative group or the like, the dye represented by Formula (1) may have a negative charge arising from dissociation. itt this case, an clcctric charge of the dye rcpresented by Formula (1) as a whole is electrically neutrahzed by the counter ion Cl. ni4 that represents the number of counter ions represented by Ci is an integer of 0 to 3.

t0068} When the counter ion Cl is a positive counter ion, examples of the counter ion Ci include an inorganic or organic ammonium ion (for example, tetraalkyl ammonium ion, pyridiniurn ion and the like), an alkali metal ion and a proton.

When the counter ion CI is a negative counter ion, the negative counter ion maybe an inorganic negative ion or an organic negative ion. Examples thereof include a halogen negative ion (for example, fluoride ion, chloride ion, bromide ion, iodide ion and the like), a substituted arylsulfonate ion (for example, p-toluene sulfonate ion, p- chlorohcnzcne sulfonatc ion and the like), an aryidisulfonatc ion (for cxarnplc, 1,3-benzene disulfonate ion, 1,5-naphthalene disulfonate ion. 2,6-naphthalene disulfonate ion and the like), an alkylsulfate ion (for example, methylsulfate ion and the like), a sulfate ion, a thioeyanate ion, a perchlorate ion, a tetrafluoroborate ion, a hcxafluorophosphae ion, a picrate ion, an acetate ion and a trifluoromethane sulfonate ion. Alternatively, as a charge balance counter ion, an ionic polymer or another dye with the opposite charge from the primary dye may be used. Alternatively, a metal complex ion (for example, bisbenzene-l.2-dithiolatonickel (Ill) and the like) may be used.

A6) Anchoring group (Interlocking group) The dye having the structure represented by Formula (1) preferably has at least one acidic group (interlocking group) that is suitable for a surface of semiconductor tine particles, further preferably from 1 to 6 interlocking groups, and particularly preferably from 1 to 4 interlocking groups. The dye preferably has an acidic group (a substituent having a dissociablc proton) such as a carboxyl group, a sulfonate group, a hydroxyl group, a hydroxamic acid group (for example, -CONITOTI). a phosphoryl group (fbr example, -OP(O)(OH)2) and a phosphonyl group (for example, -P(O)(OH)). Above all, the dye preferable has a carhoxyl group (COOH group) on the ligand. the acidic group herein means a substituent that emits a proton. An expression "to have a substituent of specific functionality" such as "to have an acidic group" means that the substituent of specific functionality is interlocked directly with a scaffold, and also that the substituent is interlocked (linked) through a predetermined linking group, within the range in which advantageous effects of the present invention are not adversely affected.

The substituent herein can represent, for example, a substituent W described below, otherwise than as specifically described: a halogen atom (e.g. a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom); an alkyl group [which rcpresents a substituted or unsubstituted linear, branched, or cyclic alkyl group, and which includes an alkyl group (preferably an alkyl group having 1 to 30 carbon atoms, e.g. methyl, ethyl, n-propyl, isopropyl, t-butyl, n-octyl, cicosyl, 2-chloroethyl, 2-cyanoethyl, or 2-ethylhcxyl), a cycloalkyl group (prefcrahly a substituted or unsubstituted cycloalkyl group having 3 to 30 carbon atoms, e.g. cyclohexyl, cyclopentyl, or 4-n-dodecylcyclohexyl), a bicycloalkyl group (preferably a substituted or unsubstituted bicycloalkyl group having 5 to 30 carbon atoms, i.e. a monovalent group obtained by removing one hydrogen atom from a hicycloalkane having 5 to 30 carbon atoms, e.g. bicyclo[l.2.2jheplan-2-yl or bicyclo2.2.2joctan-3-yl), and a tricyclo or higher structure having three or more ring structures; and an allcyl group in substituents described below (e.g. an alkyl group in an altcylthio group) represents such an alkyl group of the above concept]; an alkenyl group [which represents a substituted or unsubstituted linear, branched, or cyclic alkenyl group, and which includes an alkenyl group (preferably a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms, e.g. vinyl, allyl. prenyl, geranyl, or oleyl), a cycloalkenyl group (preferably a substituted or unsubstituted cycloalkenyl group having 3 to 30 carbon atoms, i.e. a monovalent group obtained by removing one hydrogen atom from a cycloalkene having 3 to 30 carbon atoms, e.g. 2-cyclopeiiten-1-yl group or 2-cyclohcxcn-l-yl), and a hicycloalkenyl group (which rcprcscnts a substitutcd or unsubstituted hicycloalkenyl group, preferably a substituted or unsubstituted bicycloalkenyl group having 5 to 30 carbon atoms, i.e. a monovalent group obtained by removing one hydrogen atom from a bicycloalkene having one double bond, e.g. bicyclo[2.2. 1]hcpt-2-cn-1-yl or bicyclo[2.2.2]oct-2-cn-4-yl)]; an alkynyl group (preferably a substituted or unsubstituted alkynyl group having 2 to 30 carbon atoms, e.g. ethynyl, propargyl, or a trimethylsilylethynyl group); an aryl group (preferably a substituted or unsubstituted aryl group having 6 to 30 carbon atoms. e.g. phenyl, p-tolyl, naphthyl, m-chlorophenyl, or o-hexadecanoylaminophenvl); an aromatic group (e.g. a henzcne ring, a furan ring, a pyrroic ring, a pyridinc ring, a thiophcne ring, an imidazolc ring, an oxazole ring, a thiazole ring, a pyrazole ring, an isoxazole ring, an isothiazole ring, a pyrimidine ring, a pyrazine ring, or rings formed by condensation of the foregoing rings); a heterocyclic group (preferably a monovalent group obtained by removing one hydrogen atom from a substituted or unsubstituted 5-or 6-membered aromatic or nonaromatic heterocyclic compound; more preferably a 5-or 6-membered aromatic heterocyclic group having 3 to 30 carbon atoms, e.g. 2-ififyl, 2-thienyl, 2-pyrirnidinyl, 2-hcnzothiazolyl); a cyano group: a hydroxyl group; a nitro group; a carboxyl group; an alkoxy group (preferably a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, e.g. methoxy, ethoxy. isopropoxy, t-butoxy, n-octyloxy, or 2-rnethoxyethoxy); an aryloxy group (preferably a substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms, e.g. phenoxy, 2-methylphcnoxy, 4-t-hutylphcnoxy.

3-nitrophenoxy, or 2-letradecanoylaminophenoxy); a silyloxy group (preferably a silyloxy group having 3 to 20 carbon atoms. e.g. trimethylsilyloxy or t-butyldimethylsilyloxy); a heterocyclic oxy group (preferably a substituted or unsubstituted heterocyclic oxy group having 2 to 30 carbon atoms, e.g. 1-phenyltetrazol-5-oxy or 2-tetrahydropyranyloxy); an acyloxy group (preferably a formyloxy group, a substituted or unsubstituted alicylcarhonyloxy group having 2 to 30 carbon atoms, or a substituted or unsubstituted arylcarbonyloxy group having 6 to 30 carbon atoms, e.g. ffirmyloxy, acetyloxy, pivaloyloxy. stearoyloxy, henzoyloxy, or p-methoxyphenylcarbonyloxy); a carbarnoyloxy group (preferably a substiluted or unsubstituted carhamoyloxy group having ito 30 carbon atoms, e.g. N,N- dirnethylcarhamoyloxy, N,N-diethylcarbamoyloxy, morpholinocarbonyloxy, N,N-di-n-octylammocarhonyloxy, or N-n-octylcarharnoyloxy); an alkoxycarhonyloxy group (preferably a substituted or unsubstituted alkoxycarhonyloxy group having 2 to 30 1 0 carbon atoms, e.g. methoxycarhonyloxy, ethoxyearbonyloxy, t-butoxyearhony!oxy. or n-octylcarbonyhxy); an aryloxycarbonytoxy group (preferably a substituted or unsubstituted aryloxycarbonyloxy group having 7 to 30 carbon atoms, e.g. phenoxycarbonyloxy. p-methoxyphenoxycarbonyloxy, or p-n-hexadecyloxyphenoxycarbonyloxy); ai amino group (preferably an amino group, a substituted or unsubstituted alkvlamino group having ito 30 carbon atoms, or a substituted or unsubstituted anilino group having 6 to 30 carbon atoms, e.g. amino, methylarnino, dimethylarnino, anilino, N-methyt-anilino, or diphenylamino); an acylamino group (preferably a fomiylamino group, a substituted or unsubstituted alkylcarbonylamino group having I to 30 carbon atoms, or a substituted or unsuhstitutcd arylcarhonylamino group having 6 to 30 carbon atoms, e.g. formylamino, acetylarnino, pivaloylamino, laLiroylarnino, benzoylamino, or 3,4,5-tn-n-octyloxyphenylcarhonylamino); an aminocarbonylamino group (preferably a substituted or unsuhstitutcd aminocarhonylarnino group having 1 to 30 carbon atoms. c.g.

carbamoylamino, N,N-dirnethylarninocarbonylamino, K,N-dicthylaminocarbonylamino, or morpholinocarbonylarnino); an alkoxycarbonylamino group (preferably a sitbstituled orunsubstituted allcoxycarhonylaniino group having 2 to 30 carbon atoms, e.g. methoxycarhonylamino, ethoxycarhonylamino. t-hutoxycarhonylamino, n-octadecyloxycarbonylamino, or N-methyl-methoxycarbonylamino); an aryloxyearbonyl amino group (preferably a substituted or unsubstituted aryloxycarbonytarnino group having 7 to 30 carbon atoms, e.g. phenoxycarbonylamino, p-chlorophenoxycarbonylamino, or m-n-octyloxyphenoxycarhonylamino); a sulfamoylamino group (preferably a substituted or unsubstituted sulfamoylamino group having 0 to 30 carbon atoms, e.g. sulfamoylamino, N.N-dimethylaminosulfonylamino, or N-n-octylaniirtosulfonylamino); an alkyl-or aiyl-sulfonylarnino group (preferably a substituted or unsubstituted alkylsulffinylamino group having I to 30 carbon atonis, or a subsli[uted or unsubstituied arylsulfonylamino group having 6 to 30 carbon atoms, e.g. methylsulfonylamino, hutylsulfonviarnino, phenylsulfonviarnino, 2,3,5-trichlorophenylsulfonylamino, or p-methylphcnylsulfonylamino); a niercapto group; an alkylthio group (preferably a substituted or unsubstituted alkylthio group having I to 30 carbon atoms, e.g. methylthio, ethylthio, or n-hexadecylthio); an arylthio group 1 0 (preferably a substituted or unsubstituted aiylthio group having 6 to 30 carbon atoms, e.g. phenylthio, p-chlorophcnyllhio, or m-mcthoxyphcnylthio); a heterocyclic thio group (preferably a substituted or unsubstituted heterocyclic thio group having 2 to 30 carbon atoms, e.g. 2-benzothiazolylthio or l-phenyltetrazol-5-ylthio); a sulfamoyl group (preferably a substituted or unsubstituted sulfamoyl group having 0 to 30 carbon atoms, e.g. N-ethylsulfamoyl, N-( -dodecyloxypropyl)sulfamovl, N,N-dimethylsulfamoyl, N-acetylsulfamoyl, N-henzoylsulfamoyl, or N-(N'-phenylcarhamoyl)sulfamoyl); a sulfo group; an alkyl-or aryl-sulfmyl group (preferably a substituted or unsubstituted alkylsulfinyl group having 1 to 30 carbon atoms, or a substituted or unsubstituted arylsulfinyl group having 6 to 30 carbon atoms, e.g. methylsulfinyl. ethylsulfinyl, phenylsulfinyl, or p-niethylphcnylsulfinyl); an alkyl-or aryl-sulfonyl group (preferably a substitLiled or unsubstitLiled alkyisLilfonyl group having I lo 30 carbon atoms, or a substituted or unsubstituted arylsulfonyl group having 6 to 30 carbon atoms, e.g. mcthylsulfonyl, ethylsulfonyl, phcnylsulfbnyl, or p-methylphcnylsulfbnyl); an acyl group (preferably a formyl group, a substituted or unsubstituted alkylearbonyl group having 2 to 30 carbon atoms, a substituled or unsubstiluied arylcarbonyl group having 7 to 30 carbon atoms, or a substituted or unsuhstituted lieterocyclic carbonyl group having 4 to 30 carbon atoms, which is bonded to said carhonyl group through a carbon atom, e.g. acetyl, pivaloyl, 2-chloroacetyl, slearoyl, benzoyl, p-n-oetyloxyphenylcarbonyl, 2-pyridylearbonyl, or 2-finylcarbonyl); an aryloxycarbonyl group (preferably a substituted or unsubstituted aryloxyearbonyl group having 7 to 30 carbon atoms, e.g. phenoxycarhonyl, o-chlorophenoxycarbonyl, m-nitrophenoxycarbonyl, or p-t-hutyiphenoxycarhonyl); an alkoxycarhonyl group (preferably a substituted or unsubstituted alkoxycarbonyl group having 2 to 30 carbon atoms, e.g. methoxycarbonyl, ethoxycarbonyl, t-hutoxycarbonyl, or n-octadeeyloxyearhonyl); a carbarnoyl group (preferably a substituted or unsubstituted carhamoyl group having I to 30 carbon atoms, e.g. carbamoyl, N-methylcarbamoyl, N,N-dimethylcarbamoyl, N,N-di-n-octylcarharnovi, or N-(methylsulfonyl)carhamovl); an aiyl-or heterocyclic-azo group (preferably a substituted or unsubstituted aiyl azo group having 6 to 30 carbon atoms, or a substituted or unsubstituted heterocyclic azo group having 3 to 30 carbon atoms, e.g. phenylazo. p-chlorophenylazo. or 5-ethylthio-1,3,4-thiadiazol-2-ylazo); an imido group (preferably N-succinirnido or N-phthalimido); a phosphino group (preferably a substituted or unsubstituted phosphino group having 2 to 30 carbon atoms, e.g. dirnethyiphosphino, diphenylphosphino, or methyiphenoxyphosphino): a phosphinyl group (preferably a substituted or unsubstituted phosphinyl group having 2 to 30 carbon atoms, e.g. phosphinyl, dioctyloxyphosphinyl, or diethoxvphosphinyl); a phosphinyloxy group (preferably a substituted or unsubstituted phosphinyloxy group having 2 to 30 carbon atoms, e.g. diphenoxyphosphinyloxy or dioctyloxyphosphinyloxy); a phosphinylamino group (preferably a substituted or unsubstituted phosphinylarnino group having 2 to 30 carbon atoms, e.g. dimethoxvphosphinylamino or dirnethylaminophosphinylaniino); and a silyl group (preferably a substituted or unsubstituted silyl group having 3 to 30 carbon atoms, e.g. trirncthylsilyl, t-bu tyldimeihylsilyl, or phenyldimethylsilyl).

The substituent may he further substituted, in that case, examples of the suhstitucnt include thc substituent mentioned above.

(0072} In the preseni invention, among the compounds represented by ForrnLrla (1), compounds, in which Mz is Ru, ml is 1, rn2 is I, X is an isothiocyanate group, and m3 is 2, are prefcrahle Specific examples of the dye having the structure represented by Formula (I) used in the present invention are shown below. However, the present invention is not limited thereto. In the case where the dye in the following specific examples thereof contains a ligand having a proton-dissociahie group, the ilgand may release a proton with dissociation as needed.

0C5H13 (S1OMe C8H1aC ---% N MSOJZ3L'%tCYC) rN': NCS CN NCS HO2CLrjh4i HO2C'rjt X-22 CO2H -23 CO2H

NCS

N: \NCS HO2C N -Nr:Ncs -HOzCZ"t.l -CO2H HO2C X--24 co2u L) X 25 X-26 CO2NBU4 rICH Ht

-it N1NCS

-N

-w": NCS rC'N" wcs HOaC HO2C y X-27 CO2H X-28 CO2H (0075} O0?H

HC

LNJ SON1 X-30

OO,H CO2FI EIO15 HO -

N

SCNPN 32 ( N(n05H1)2 S. N(nCH13),

S 1-i

X-31 X-32 CO2H 002H r-nCHii

N

N

SON N1 1Ru

SON N

NOS

GS

nC5Hii nC H X-33 X-34 -[0076}

-I -j

C2 F-I5 -N,,. NCS

NCS

IJ HO2C CO2H X-35

f0077} C5H1 in CO2H 2H I 1 nCH11 HOzC'Ru.' N SCN1 I nC5H1

NCS C 02H X-36

As a method for synthesizing the dye represented by Formula (1). the methods disclosed in EXAMPLES as described later can be referred to, and the dye can be synthesized by appropriately applying an ordinary method based on them. Further, the dye can be synthesized with reference to the methods in the literatures of J. Am. Chem. Soc., vol. 121, p. 4047 (1997), Can. J. Chem., vol. 75, p. 318 (1997), lnorg. Chem., vol. 27. p. 4007 (1988) or the like, and the methods cited in the literatures. The dye and the methods described above are incorporated herein by reference. Moreover, the information disclosed in JP-A-2001-291534 and WO 2007/091525 can also be referred to, and the dye and the methods described above are incorporated herein by reference.

{ 00791 The dye represented by Formula (1) has a maximum absorption wavelength in a solution in a range of preferably from 300 nm to 1,000 mit more preferably from 350 nrn to 950 nm, and especially still more preferably from 370 mu to 900 11111.

(0080} The content of the dye represented by Formula (1) herein is not particularly limited, but is preferably 0.001 to I millimole, and further preferably 0.1 to 0.5 millimole, based on I g of the semiconductor fine particles. When the content is adiusted to he equal to or more than the lower limit, a sensitizing effect in the semiconductor can be sufficiently achieved. When the content is adjusted to be eqLtal to or less than the upper limit, reduction of the sensitizing effect as caused by desorption of the dye can be suppressed. Moreover, two or more kinds of dyes represented by Formula (1) may be used in the present invention.

(B) Charge transfer layer A layer formed of an electrolyte composition can be applied to the charge transfer layer used thr the photoelectric conversion element according to the present S embodiment. Examples of the redox pair include a combination of iodine and an iodide (for example, lithium iodide, tetrabutylammonium iodide, or tetrapropylainmonium iodide), a combination of an alkylviologen (for example, methylviologen chloride, hexylviologen bromide, or henzylviologen tetrafluorohorate) and a reductant thereot a combination of polyhydroxybenzenes (for example, hydroquinone or naphthohydroquinone) and an oxidant thereot and a combination of a divalent iron complex and a trivalent iron complex (for example. potassium ferricyanide and potassium ferrocyanide). Among these, a combination of iodine and an iodide is preferred.

A cation of iodine satt is preferably a 5-or 6-membered nitrogen-containing aromatic cation. In particular, when the compound represented by Formula (1) is not the iodine salt. an iodine salt such as the pyridinium salt, the imidazolium salt, and the triazolium salt as described in WO 95/18456, JP-A-8-259543, and Electrochemistry, vol. 65, No. 11, p.923 (1997), is preferably used in combination.

In the electrolyte composition used for the photoelectric conversion element, iodine is preferably contained with a heterocyclic quaternary salt compound. The cornent of iodine is preferably 0.1 to 20% by mass, and further preferably 0.5 to 5% by mass, based on the total of the electrolyte composition.

(0082} The electrolyte composition may contain a solvent The content of the solvent in the electrolyte composition is preferably 50% by mass or less, further pre!èrably 30% by mass or less, and particularly preferably 10% by mass or less, based on the total of the composition.

The solvent preferably can develop excelleni ion conductivity due to low viscosity to have high ionic mobility, or high permittivity to allow an increase in an effective carrier concentration, or due to satisfying both properties. Specific examples of such solvents include a carbonate compound (e.g. ethylene carbonate and propylene carbonate), a heterocyclic compound (e.g. 3-methyl-2-oxazolidinone). an ether compound (e.g. dioxane and diethyl ether), chain ethers (e.g. ethylene glycol dialkyl ether, propylene glycol dialkyl ether, polyethylene glycol dialkyl ether, and polypropylene glycol dialkyl ether), alcohols (e.g. methanol, ethanol, ethylene glycol monoalkyl ether, propylene glycol monoalkyl ether, polyethylene glycol monoalkyl ether, and polypropylene glycol monoalkyl ether), polyhydric alcohols (e.g. ethylene glycol, propylene glycol, polyethylene glycol, polypropylene glycol, and glycerol), a nitrile compound (e.g. acetonitrile, glutarodinitrile, methoxyacetonitrile, propionitnle.

benzonitrile, and hiscyanoethyl ether), esters (e.g. carboxylate, phosphate, and phosphonate), an aprotie polar solvent (e.g. dimethyl sulfoxide (I)MSO) and sulfolane), water, a water-containing electrolytic liquid as described in JP-A-2002-110262, and an electrolytic solvent as described in.fP-A-2000-36332. JP-A-2000-243 134 and WO 00/54361. These solvents may be used by mixing two or more kinds.

t0083} Moreover, as the electrolytic solvent, an electrochemically inert salt that is in a liquid state at room temperature and/or has a melting point lower than room temperature may also be used. Specific examples include an imidazoliurn salt such as l-ethyl-3-methylimidazolium thfluoroinethanesulfonate and 1 -butyl-3-methylimidazolium tritluoromethanesulfonate, a nitrogen-containing heterocyclic quaternary salt compound such as a pyridiniurn salt. and a tetraalkylammonium salt.

{ 0084} The electrolyte coniposition may also be allowed to gelate (solidified) by adding a polymer or an oil-gelling agent, or by applying a technique such as polymerization of polyftmctional monomers or a polymer crosslinking reaction. {0085

In the case where the electrolyte composition is allowed to gelate by adding a polymer, compounds described in "Polymer Electrolyte Reviews I and 2' (edited by J. R. MacCallum and C. A. Vincent, ELSEVIER APPLIED SCIENCE), can be used as the polymer. Of these compounds, polyacrylonitrile or poly(vinylidene fluoride) is preferably used.

{ 0086 In the case where the electrolyte composition is allowed to gelate by adding an oil-gelling agent, compounds described in J. Chem. Soc. Japan, md. Chem. Soc., 1943, P. 46779; J. Am. Chem. Soc., 198S,vol. 111, p.5542; 1. Chem. Soc., Chem. Commun., 993, p. 390; Angew. Chern. mt. Ed. EngI., 1996, vol. 35, p. 1949; Cheni. Lett., 996, p. 885; J. Chern. Soc., Chem. Commun.. 1997, p. 545; or Ihe like can be used as the oil-gelling agent. Of these compounds, a compound having an amide structure is prcferahly used.

t0087} In the case where the electrolyte composition is allowed to gelate by polymerization of polyftmctional monomers, a method is preferably applied in which a solution is prepared from polyffinctional monomers, a polymerization initiator, an electrolyte, and a solvent, a sol electrolyte layer is foniied on a dye-supported electrode by a method such as a cast method, an application method, an immersion method, and an impregnation method, and then the electrolyte layer is allowed to gelate by radical polymerization of the polyfunctional monomer. The polvfunctional monomer is prcfcrahly a compound having two or more ethylenically unsaturated groups. Preferred examples thereof include divinylbenzene, ethylene glycol diacrylate, ethylene glycol dimethacrylate, diethylene glycol diacrylate, diethylene glycol dimethacrylate, triethylene glycol diacrylate, triethylene glycol dimethacrylate, pentaerythritol triacrylate, and trimethylolpropane triacrylate.

The gel electrolyte may also be foniied by polymerization of a mixture containing a nionofunctional monomer in addition to the polyfunctional monomers.

Examples of the monofunctional monomer include acrylic acid or ct-alkylacrylic acid (e.g. acrylic acid, methacrylic acid, and itaconie acid) or ester or amide thereof (e.g. methyl acrylate, ethyl aciylate, n-propyl acrylate, i-propyl acrylate, n-hutvl acrylate, I- hutyl acrylate, t-hutyl aciylate, n-pentyl aerylate, 3-pentyl acrylate, t-pentyl aerylate, n- hexyl aerylate, 2,2-dimethylbulyl acrylale, n-octyl acrylale, 2-elhylhexyl acrylate, 4-methyl-2-propylpentyl aciylate, cetyl acrylate, n-octadecyl acrylate, cyelohexyl aerylate, cyclopentyl aciylate, benzyl acrylate, hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-methoxyethyl acrylate, 2-ethoxyethyl aerylate, 2-methoxyethoxyethyl acrylate, phenoxyethyl acrylate, 3-methoxyhutyl acrylate. ethylcarhitol acrylate, 2-methyl-2-nitropropyl acrylate, 2,2,2-trifluoroethyl acrylate, octafluoropentyl acrylate, heptadecafluorodecyl acrylate, methyl methacrylate, n-butyl met hacrvlate. i-hutyl niethacrylate, t-hutyl methacrylate. t-pentyl methacrylate, n-octadecyl methacrylate, benzyl methacrylale, hydroxyethyl methacrylale, 2-hyclroxypropyl methacrylate, 2-methoxyethyl methacrylate, 2-ethoxyethyl inethacrylate, 2-methoxyethoxyethyl methacrylate, dirnethylaminoethyl methacrylate, 2,2,2-trifluoroethyl methacrylate, tetrafluoropropyl rnethacrylate. hexafluoropropyl niethacrylate, heptadecafluorodecyl methacrylate, ethyleneglycolethyl carbonate methacrylate, 2-isobornyl methacrylate, 2- 1 0 norbornylmethyl niethaciylate. 5-norbornen-2-ylmethyl rnethaciylate, 3-methyl-2-norbornylmethyl methacrylate. acrylamide, N-i-propylacrylamide, N-n-butylacrylamide, N-t-butyl-acrylarnide, N,N-dirnethylacrylarnide, N-rnethylolacrylarnide, diacetonacrylamide, 2-acrylamide-2-methylpropanesulfonic acid, acrylamide propyltrimethylammoniurn chloride, methacrylarnide, N-rnethylmethacrylamide, N-methylolmethacrylamide), vinyl esters (e.g. vinyl acetate), maleic acid or fumaric acid, or esters derived from maleic acid or fumaric acid (e.g. dimethyl malcate, dihutyl mateate. and diethyl fumarate), a sodium salt of p-styrenesulfonic acid, acrylonitrile, methacryloniu-ile, dienes (e.g. hutadiene, cyclopentadiene, and isoprene), an aromatic vinyl compound (e.g. styrene, p-chlorostyrene, t-butylstyrene, a-methylstyrene, and sodium styrenesulfonate). N-vinylformamidc, N-vinyl-N-niethylformamide. N-vinylacetarnide, N-vinyl-N-rnethylacetarnide. vinylsulfonic acid, sodium vinylsulfonale, sodium allylsulfonate, sodium methacrylsulfonate, vinylidene fluoride, vinylidene chloride, vinyl alkyl ethers (e.g. methyl vinyl ether), ethylene, propylene. butane, isobutene, and N-phenylmaleimide {0089 The amount of the polyfunctional monomer component is preferably 0.5 to 70% by mass, and thither preferably 1.0 to 50% by mass, based on the total of monomers. The monomer can be polymerized according in radical polyrnerizalion being an ordinary macromolecule synthesis method described in "Kobunshi (Josei no Jitcken Hou (Experimental methods of potymer synthesis)," co-edited by I'akayuki OTSTJ and Masayoshi KJNOSHITA (Kagaku-Dojin Publishing Company, Inc.), and "Koza Jugo Flannou Ron I (Polymerization reaction theory course I), Radical polymerization (1))" by Takayuki OTSU (Kagaku-Dojin Publishing Company, Inc.).

The monomer for the gel electrolyte used in the present invention can he radically polyrnenzed by heating, light or an electron beam, or electrochernically, hut particularly preferably polymerized by heating. In this case, examples of the polymerization initiator that can he preferably used includes an azo initiator such as 2,2 azobisisobutyronitrile, 2,2'-azohis(2,4-dirnethylvaleronitrile), dimethyl-2,2'-aohisci2-niethylpropionate). and dimethyl-2,2'-azohisisohutyrate; and a peroxide initiator such as lamyl peroxide, benzoyl peroxide and t-hutyl peroxyoctoate. A preferred amount of polymerization initiator addition is (J.0l to 20% by mass, and a frirther preferred amount is 0.1 to 10% by mass, based on the total amount of monomer.

The weight composition oftlie mononier in the gel electrolyte is preferably in the range of 0.5 to 70% by mass, and further preferably in the range of 1.0 to 50% by mass. In the case where the gel electrolyte composition is prepared by the polymer crosslinking reaction, a polymer having a crosslinkable reactive group and a crosslinking agent are preferably added to the composition. A preferred reactive group includes a nitrogen-containing heterocyclic ring such as a pyridine ring, an imidazole ring, a thiazole ring, an oxazole ring, a triazole ring, a morpholine ring, a piperidine ring and a piperazine ring. A preferred crosslinking agent includes a compound electrophi1e) having two or more functional groups to which the nitrogen atom can make a nucleophilic attack. Specific examples include alkyl halide, aralkyl halide, sulfonate, acid aniiydride, acid chloride and isocyanate having two or more functional groups.

(0090} To the electrolyte composition, metal iodide (e.g. LW, NaT. KI. CsI and Cal,), metal bromide (e.g. l;iflr, NaBr, KUr, CsRr and Caflr2), quaternaty ammoniuni bromide (e.g. tctraalkylammonium bromide and pyridinium bromide), a metal complex (e.g. ferrocyanale-ferricyanate and ferrocene-ferriciniurn ion), a sLIlfLtr compound (e.g. poly(sodium sulfide) and alkyl thiol-alkyl disulfide), a viologen dye, hydroquinone-quinone. or the like may be added. These may be used by mixing with each other.

In the present invention, moreover, a basic compound such as t-hutylpyridine, 2-picoline, and 2,6-lutidin described in J. Am. Ceram. Soc., 1997, vol. 80, No. 12, p. 3157-317 may also he added. A prefelTed concentration iii the case of adding the basic compound is in tile range of 0.05 to 2 M. As the electrolyte, a charge transport layer containing a hole conductor material may also be used. As the hole conductor material, a 9.9'-spirobifluorene derivative or the like can he used.

f0092} (C) Electrically conductive support As the electrically conductive support, a support having electroconductivity per se, such as a metal, or a glass or polymeric material having an electrically conductive layer on thc surfacc can be used. it is preferable that thc electrically conductivc support is substantially transparent. The terms "substantially transparent" means that the transmittance of light is 10% or more, preferably 50% or more, particularly preferably 80% or more. As the electrically conductive support, a support formed from glass or a polymeric material and coated with an electrically conductive metal oxide can be used.

In this case, the amount of coating of the conductive metal oxide is preferably 0.1 to g per square meter of the support made of glass or a polymeric material. In the case of using a transparent conductive support, it is preferable that light is incident from the support side. Examples of the polymeric material that may be preferably used include tctraacetyleellulose (TAC), polyethylene terephthalate (PET), polyethylene naphthalatc (PEN), syndiotactie polystyrene (SPS), polyphenylene sulfide (PPS), polycarbonate (PC), polyaiylate (PAR), polysulfone (PSF), polyester sulfone (PBS), polyetiier irnide (PEI). cyclic polyolcfin, and phcnoxy bromide. The electrically conductive support may be provided with a light management function at the surface, and for example, the anti-reflective film having a high refractive index film and a low refractive index oxide film alternately laminated as described in JP-A-2003-123859, and the light guide function as described in JP-A-2002-260746 may he mentioned.

In addition to the above, a metallic support can also be preferably used.

Examples thereof include titanium, aluminum, copper, nickel, iron, stainless steel and copper. these metals may be alloys. Among these. titanium, aluminum and copper are further preferable; and titanium and aluminum are particularly preferable.

It is preferable to provide the electrically conductive support with a function of blocking ultraviolet light. For instance, there may be mentioned a method of adopting a fluorescent material that is capable of changing ultraviolet light to visible light, within the polymeric material layer or on the surface of the polymeric material layer. As another preferred method, a method of using an ultraviolet absorbent may also be used.

The conductive support may also be imparted with the ftmctions described iii JP-A-1 1-250944.

Preferred examples of the electrically conductive film include films of metals (for example, platinum, gold, silver, copper, aluminum, rhodium, and indium), carbon.

and electrically conductive metal oxides (for example, indium-tin composite oxide, and fluorine-doped tin oxide).

The thickness of the conductive film layer is preferably 0.01 to 30 jim, more preferably 0.03 to 25 jim, and particularly preferably 0.05 to 20 jim.

In the present invention, an electrically conductive support having lower surface resistance is preferred. [he surface resistance is preferably in the range of 50 0/cm2 or less, and more preferably 10 0/em2 or less.. The lower limit of the surface resistance is not particularly limited, but the lower limit is usually about 0.1 0/cm2.

f0095} Since the resistance value of the electrically conductive film is increased as the cell area increases, a collecting electrode may be disposed. A gas barrier film arid/or an ion diffusion prcvcnting film niay he disposed between the support and the transparent conductive film. As the gas barrier layer, any of a resin film or an inorganic film can be used.

Furthermore, a transparent electrode and a porous semiconductor electrode photocatalyst-containing layer may also he provided. The transparent conductive layer may have a laminale structure, and preferred examples of the production method include the method of laminating ETO on ITO.

{0096} (DI) Semiconductor fine particles The semiconductor fine particles locally have two or more kinds of metals or metallic compounds. In the present invention, the metallic compound means an inorganic compound containing a metal and at least one kind of atom other than the nietal in a molecule. Specific examples include metal chalcogenide, metal carbonate. or metal nitrate. In the present invention, the semiconductor fine particles locally having two or more kinds of metals or metallic compounds mean those in which two or more kinds of metals or metallic compounds locally exist in the fine particles by treating the fine particles with two or more kinds of metals or metallic conipounds Specific examples of the semiconductor fine particles locally having two or more kinds of metals or metallic compounds include, as described later, those in which a core-shell structure is formed by two or morc kinds of mctals or metallic compounds, or those in which part of the sw-face and other parts are formed of different metals or metallic compounds.

Therefore, a simple mixture of two or more kinds of semiconductor fine particles is not included. When a dye having a specific substituent is used for the semiconductor fine particles locally having two or more kinds of metals or metallic compounds, the dye can he effectively adhered on the semiconductor fine particles., and thus a highly durable photoelectric conversion element can be realized.

The semiconductor fine particles preferably have a metal atom, metal chalcogenidc, metal carbonate and/or metal nitrate.

The metal atom is preferably at least one kind selected from the group consisting of Ti (titanium), Sn (tin), Au (gold), Ag (silver), Cu (copper), Al (aluminum), Zr (zirconium), Nb (niobium), V (vanadium), and Ta (tantalum) Thc metal atom is further preferably Ti, Sn, Zr, Nb, V or Ta; and particularly preferably Nb, V or Ta.

The metal chalcogenide is preferably cadmium sLLllide, cadmium selenide, or an oxide of at least one kind of metal selected from the group consisting of Ti (titanium), Sn (tin). Zn (zinc), Mg (magnesium). Al (aluminum), W (tungsten), Zr (zirconium), Hf (hafiuium). Sr (strontium), In (indium), Ce (cerium), Y (yttrium), La (lanthanLnn), V (vanadium), and Ta (tantalum): lìtrther preferably an oxide of at least one kind of metal selected from the group consisting of Ii, Sn, Zn, Mg and At; still further preferably an oxide of at least one kind of metal selected from the group consisting of Ti, Sn, Mg and Al; and particularly preferably an oxide of at least one kind of metal selected from the group consisting of Ti, Sn and Al.

The metal carbonate is preferably at least one ldnd selected from the group consisting of calcium carbonate, potassium carbonate, and barium carbonate. The metal carbonate is further preferably calcium carbonale or barium carbonate, and particularly preferably calcium carbonate.

The metal nitratc is preferably lanthanum nitrate.

t0098} The semiconductor tine particles locally having two or more kinds of metals or metallic compounds preferably have the core-shell structure, and frirther preferably have the metal atom, the metal chalcogenide, the metal carbonate, and/or the metal nitrate by the core-shell structure. "Core-shell structure" herein means one having a shell (outer shell) part so as to cover the core pan being the core. The core part does not need to be wholly covered with the shell part, but preferably 50% or more, thrther preferably 80% or more, and particularly preferably 90% of a surface area of the core part is covered with the shell part. The semiconductor fine particles having the core-shell structure can produce an effect of improving open circuit voltage by action of suppressing electrons injected from an excited dye from returning to l-in the electrolytic liquid.

{ 00991 The semiconductor tine particles having the core-shell structure can he obtained by adding semiconductor fine particles to be formed as the core into a solution of the metal atom or the metallic compound to be formed as the shell, and allowing the semiconductor fine particles to appropriately react with the metal atom or the metallic compound. The semiconductor fine particles to be formed as the core may be used in one kind or two or more kinds thereof and the metal atom and the melallie compound to he formed as the shell can he used in one kind or two or more kinds thereof As the semiconductor fine particles having the core-shell structure, for example, semiconductor fine particles having a core-shell structure in which titanium oxide is contained as the core and calcium carbonate is contained as the shell can be prepared by the method described below, but preparation is not limited to this method and the conditions. First, 12 g (0.2 ntol) of acetic acid is added dropwise to 58.6 g (0.2 mol) of titanium tetraisopropoxide while stirring the resultant mixture with a stirrer. The mixture obtained is stilTed for 15 minutes, and added to 290 mL of distilled water.

After stirring for 1 hour, 4 ml, of 65% nitric acid is added, the resultant mixture is heated to 78°C over 40 minutes to keep a constant temperature for 75 minutes. A reaction vessel is removed from a healer, and 370 mL of waler is added thereto. The liquid obtained is transferred into an autoclave made from titanium, and heated at 250°C for 12 hours. Then, 2,4 ml of 65% nitric acid is addcd, the resultant mixture is stirred by means of an ultrasonic homogenizer, and then a dispersion liquid is concentrated until the amount of titanium oxide reaches 13 to 15%. The concentrated solution is centrifogally separated, supernatant distilled water is removed, and an amount of ethanol same with thc amount of distilled water is addcd. [hen. thc resultant mixture is stined by means of an ultrasonic homogenizer, and thus the dispersion liquid of titanium oxide as the core is obtained. Next, the titanium oxide particles being the core are added to an aqueous solution of 1 to 3% by mass of calcium acetate, and the resultant mixture is stirred for 30 minutes to 3 hours. After stirring, the calcium acetate aqueous solution is removed by centrifugal separation, and the remaining solid is washed with distilled water to perform centriffigal separation, and the resultant solid is calcined at 525°C for 1 hour. Thus, the semiconductor fine particles having the core-shell structure in which titanium oxide is contained as the core and calcium carbonate is contained as the shell can he obtained.

The semiconductor fine parlicles obtained can be judged 10 have the core-shell structure by observation by means of a transmission electron microscope (TEM). A volume ratio oftlie core part to the shell part is not particularly limitcd, bitt thc volume ratio is preferably 50:50 to 98:2, and further preferably 70:30 to 95:5. The volume ratio can be determined by observation by means of TEM. 1 004

The semiconductor fine particles having the core-shell-structure preferably have, as the core parl, a metal atom, metal chalcogenide or metal nitrate. The core pan is ftrther preferably a metal atom or metal ehalcogenide, and particularly preferably metal chalcogenide. [he shell part preferably has metal chalcogenide or metal carbonate.

When the metal atom is used as the core part, the metal atom is preferably at least one kind of metal atom selected from the group consisting of Ti, Nb, Sn, Zn and La; fttrther preferably Ti, Sn or Zn; and particularly preferably Ti or Sn. When the metal chalcogenide is used as the core part, the metal chalcogenide is preferably at least one kind of metal oxide selected from oxides of Ti, Sn, Zn, Mg and Al; further preferably an oxide of Ti. an oxide of Sn. or an oxide of Zn; and particularly preferably an oxide of Ti or an oxide of Sn. When the metal nitrate is used as the core part, the metal nitrate is preferably lanthanuni nitrate.

When the metal chalcogenide is used as the shell part, the metal chalcogenide is preferably oxides of Ii, Mg and Al. When the metal carbonate is used as the shell part. the metal carbonate is preferably calcium carbonate.

{010l} A particle diameter of the semiconductor tine particles is preferably from I nm to 1,000 nm, fiuther preferably from 2 nm to 100 nm in an average particle diameter of primary particles for the purpose of keeping high viscosity of semiconductor fine particle dispersion liquid. The particle diameter herein is a value measured by means of a laser diffraction-type particle diameter distribution analyzer, for example, Mastersizer (trade name) manufactured by Malvem Instruments Ltd. Two or more kinds of fine particles having different particle diameter distributions may he used in mixture, and in this case it is preferable that the average size of the smaller particles is 5 nm or less.

Moreover, for the purpose of enhancing a light trapping rate by scattering incident lighi, large particles having an average particle diameter exceeding 50 nm can also he added or applied as a separate layer at a low content based on the ultrafine particles described above. In this case, the content of the large particles is preferably 50% or less, and more preferably 20% or less, by mass of the content of the particles having an average particle diameter of 50 nm or less. The average particle diameter of the large particles that are added and mixed for the purpose described above is preferably 1 00 nm or more, and more preferably 250 nm or more.

{0102J In regard to the method for producing senuconductor fine particles, sol-gel methods described in, for example, SAKICA, Sumio, "Science of Sol-Gel Processes", Agne Shofu Publishing, Inc. (1998) are preferred. It is a'so preferable to use a method developed by Degussa GmhH, in which a chloride is hydrolyzed at high temperature in an acid hydride salt to produce an oxide. When the semiconductor fine particles are titanium oxide, the sol-gel method, the gel-sol niethod, and the method of hydrolyzing a chloride in an acid hydride salt at high temperature, are all prefelTed, and the sulfuric acid method and chlorine method described iii SEINO Manabu, Titanium Oxide: Material Properties and Application Technologies", Gihodo Shuppan Co, LtdJ1997) niay also he used. Other preferred examples of the sol-gel method include the method described in Barbe et al., Journal of American Ceramic Society, Vol. 80, No. 12, pp. 3157-3171 (1997), and the method described in Humside et al., Chemistry of Materials, Vol. 10, No. 9, pp. 2419-2425.

Upon manufacturing the semiconductor fine particles having the core-shell structure, as described above, the semiconductor fine particles to be formed as the core part can be first manufactured by the conventional method. For example, when titanium oxide (titania) is used for the core, the semiconductor fine particles to he formed as the core part arc manufactured according to a method for manufacturing titania nanoparticles, preferably, a method by flame hydrolysis of titanium tetrachloride, a method of titanium teftachloride combustion, hydrolysis of a stable chalcogenide complex, hydrolysis of orthotitanic acid, a method for dissolving and removing a soluble part, after forming semiconductor fine particles, from the soluble part and an insoluble part, and hydrothermal synthesis of a peroxide aqueoLls solution. Then, the semiconductor fine particles of the core-shell sfructure are obtained by adding, to the solution of thc mctal atom or metallic compound to he served as thc shell. thc semiconductor fine particles to be served as the core by the method described above and allowing a suitable reaction.

Examples of the crystal structure of titania being the core pail include anatase type brookite type, and rutile type and anatase type and hrookite type structures are preferred in the present invention. 11 is also acceplable to mix a titania nanotube/nanowire/nanorod with the titania fine particles.

fOlO3} The semiconductor fine particles locally having two or more kinds of metals or metallic compounds. to he used in the present invention. may he semiconductor fine particles prepared so as to have two or more kinds of metal atoms by doping the metal atom into semiconductor fine particles. When the metal atom is doped, an effect of an increase of short-circuit current can he produced by action of iniproving electric charge injeclion efficiency due to a posilive shill of flat band potenlial.

Specific examples of the metal atom to be doped include Nb, V and Ta. Nb or V is ifirther preferred. For example, Nb powder and tetrabutyl titanate are added to an aqueous solution containing hydrogen peroxide and amnioma (v/v = 5/1), and the resultant mixture is stirred. After stirring, excess hydrogen peroxide arid ammonia are removed by heating to 80°C. the solution obtained is transferred into an autoclave made from teflon (registered trade name), and stirred at 180°C for 20 hours. Ihe precipitate obtained is washed with distilled water having pIT = 7 and dried at 100°C for 6 hours, and thus the metal atom can be doped.

tO 104) The semiconductor fine particles may include an additive other than the metal atom, the metal chalcogenide, the mctal carbonate, and the metal nitrate. As the additive. an electrically conductive material is preferred. Specific examples of the electrically conductive material include an application-type electrically conductive material. Specific examples include a carbon material such as a carbon nanotuhe, graphene and graphite; a a-conjugated polymer being an electrically conductive polymer; and a silver nanowire. These materials can be formed by applying a thin film to develop electrical conductivity, and thus the semiconductor fine particles can he manufacturcd at a low cost. Among the niatcrials. a carbon material such as graphite, graphene and a carbon nanotube is preferred, and graphene is further preferred. When the electrically conductive material is added to the semiconductor line particles, the above-described dye excited by light irradiation can be held as it is, a reaction of returning the dye to a ground state can he suppressed, and thus cell performance, particularly photoelectric conversion efficiency, can be improved. Graphite or graphene having a planar structure is further preferred. The additives such as the electrically conductive material can be added to the semiconductor fine particles by adding the additive to a paste of semiconductor fine particles and then applying a method for dispersing the resultant mixture by means of the ultrasonic homogenizer. As the electrically conductive material, one having a value of electric resistance of to7 L}cm or less is preferred, and one having a value of IcY 0_cm or less is further preferred.

In addition thereto, a binder for improving necking of the semiconductor tine particles with each other may be used, or an additive may also be used on the surface for preventing reverse electron transfer, for the semiconductor fine particles. Preferred examples of the additive include ITO or SnO particle5,whiskers, a fibrous graphite/carbon nanotuhe, a zinc oxide necking coupler, fibrous materials such as celluloses, metals. organosilicon, dodecyl benzenesulfonate, charge transfer coupling molecules of silane compounds or the like, and a potential gradient type dendrimer. For the purpose of eliminating surface defects of semiconductor fine particles, the semiconductor fine particles niay be subjected to an acid base treatment or an oxidation reduction treatment before the adsorption of a dye. Furthermore, the semiconductor fine particles may also be subjected to etching, an oxidation treatment, a hydrogen peroxide treatment, a dehydrogenation treatment, UV-ozone, oxygen plasma or the like.

{01 05} the semiconductor fine particles locally having two or more kinds of metals or metallic compounds, to he used in the present invention, are preferably semiconductor fine particles having a core-shell structure that has metal ehaleogenide as the core part and metal ehaleogenide or metal carbonate as the shell part. or semiconductor fine particles obtained by doping the metal atom into metal ehaleogenide; and more preferably semiconductor fine particles having a core-shell structure that has metal chalcogenide selected from the group consisting of titanium oxide (TiC)2) and tin oxide (Sn02) as the core part and metal chaleogenide or metal carbonate selected from the group consisting of aluminum oxide (A1203), maesium oxide (MgO), calcium carbonate (CaCO1), titanium oxide (Ti02), and titanium oxide/magnesium oxide (Ti02/MgO) as the shell part, or semiconductor fine particles obtained by doping at least one kind of metal atom selected from the group consisting of Nb, V and Ta into metal chaleogenide selected from the group consisting of titanium oxide and tin oxide.

(0106) (IF) Preparation of semiconductor fine particle dispersion liquid and production of semiconductor fine particles-coated layer A semiconductor fine particles-coated layer can be obtained by applying a semiconductor fine particle dispersion liquid on the electicalIy conductive support mentioned above, and appropriately heating the coated support In the semiconductor fine particle dispersion liquid, it is preferable that the content of solids excluding the semiconductor fine particles is 10% by mass or less of the total amount of the semiconductor fine particle dispersion 1 quid.

Exaniples of the method of producing a semiconductor fine particle dispersion liquid include, in addition to the sol-gel method described above, a method of 1 0 precipitating the semiconductor in the form of fine particles in a solvent upon synthesis and dircctly using the fine particles; a method of ultrasonicating fine particles, and thereby pulverizing the tine particles into ultrafine particles; a method of mechanically grinding a semiconductor using a mill or a mortai; and pulverizing the ground semiconductor; and the like. As a dispersion solvent, water and/or various organic solvents can be used. Examples of the organic solvent include alcohols such as methanol, ethanol, isopropyl alcohol. citronellol and a-terpineol; ketones such as acetone; esters such as ethyl acetate; dichloromethane, and acetonitrile.

At the time of dispersing the fine particles, for example, a polymer such as polyethylene glycol, hutykellulose, ethylcellulose. hydroxyethyleellulose or carhoxymethylcellulose; a surfaetant; an acid; or a chelating agent may he used in a small amount as a dispersing aid, as necessary. It is preferable that such a dispersing aid is mostly eliminated before the step of forming a film on the electrically conductive support, by a filtration method, a method of using a scparating membrane, or a centriffigation method. The semiconductor fine particle dispersion liquid is such that the content of solids excluding senñconduelor line particles is 10% by mass or less based on the total amount of the dispersion liquid. This concentration is preferably 5% or less, fttrther preferably 3% or less,further preferably 1% or less, farther preferably 0.5% or less, and particularly preferably 0.2% or less. In other words, the semiconductor fine particle dispersion liquid may contain a solvent and solids excluding semiconductor fine particles in an amount of 10% by mass or less based on the total amount of the semiconductor fine particle dispersion liquid. In the present, it is preferable that the semiconductor fine particle dispersion liquid issubstanally composed of semiconductor fine particles and a dispersion solvent.

If the viscosity of the semiconductor fine particle dispersion liquid is too high, the dispersion liquid undergoes aggregation, and film thrmation cannot he achieved.

On the oLher hand, ii' the viscosity of the semiconductor line particle dispersion liquid is too low, the liquid flows out, and film formation cannot be achieved in some cases.

Therefore, the viscosity of Ihe dispersion liquid is preferably 10 to 300 N-s/m2 at 25°C, and more preferably 50 to 200 N-s/rn2 at 25°C.

In regard to the method of applying the semiconductor fine particle dispersion liquid, a roller method, a dipping method or the like can be used as a method involving application. Furthermore, an air knife method, a blade method or the like can be used as a method involving metering. As a method that can equally utilize a method involving application and a method involving metering, a wire bar method disclosed in JP-B-58- 4589 ("JP-B" means examined Japanese patent publication), an extrusion method, a curtain method and a slide hopper method described in U.S. Patent No. 2,681,294 and the like are preferred. it is also preferable to apply the dispersion liquid by a spinning method or a spray method, using a versatile machine. Preferred examples of a wet printing method include the three major printing methods of relief printing, offset printing and gravure printing, as well as intaglio printing, rubber plate printing, screen printing and the like. Among these, a preferable film forming method is selected in accordance with the liquid viscosity or the wet thickness. Furthermore, since the semiconductor fine particle dispersion liquid used in the present invention has high viscosity and has viscidity, the fine particle dispersion liquid often has a strong cohesive power, and may not have good aftinity to the support upon coaling. Under such circumstances, when surface cleaning and hydrophilization are carried out through a 1W-ozone treatment, the affinity between the applied semiconductor fine particle dispersion liquid and the surface of the elecirieally conductive support increases, and thus it becomes easier to apply the semiconductor fine particle dispersion liquid.

the thickness of the entire semiconductor fine particle layer is preferably 0.1 to more preferably Ito 30 tm, and even more preferably 2 to 25 pm. The amount of the coated semiconductor fine particles per square meter of the support is preferably 0.5 to 400 g, and more preferably 5 to 100g.

{01 08} The applied layer of semiconductor fine particles is subjected to a heating treatmeni, for the purpose of reinforcing the electronic conlact between semiconductor fine particles and enhancing the adhesiveness of the semiconductor fine particles to the support, and also in order to diy the applied semiconductor fine particle dispersion liquid The porous semiconductor fine particle layer call he formed by this heating treatment. In addition thereto, according to characteristics and an application of a member, the semiconductor fine particle layer may be appropriately formed by a known method. For example, a material, a preparation method, and a production method disclosed in JP-A-2001 -291 534 can be referred to, and are incorporated herein by reference.

Furthermore, light energy can also be used in addition to the heating treatment.

For example, when titanium oxide is used for the semiconductor fine particles, the surface may he activated by providing the light that is absorbed by the semiconductor fine particles, such as ultraviolet light, or only the surface of the semiconductor fine particles can be activated with a laser light or the like. When the semiconductor fine particles are irradiated with a light that is absorbed by the fine particles, the impurities adsorbed to the particle surthccs are decomposed as a result of activation of the particle surfaces, and a state preferable for the purpose described above can be attained. In the case of using the heating UeaUnent and ultraviolet light in combination, the heating is carried out at a temperature of preferably 100°C or more and 250°C or less, more preferably 100°C or more and 150°C or less, while the semiconductor fine particles are nTadiated with the light that is absorbed by the fine particles. As such, by inducing photoexcitation of the semiconductor fine particles, the impurities incorporated in the fine particle layer can he washed away by photodecoinposition, and the physical bonding between the fine particles can be reinforced.

{0109J In addition to the processes of applying the semiconductor fine particle dispersion liquid on the electrically conductive support and subjecting the semiconductor fine particles to heating or light irradiation, other treatments may also he carried out. Preferred examples of such treaftuents include the passage of electric current, chemical treatment, and the like.

It is also acceptable to apply pressure after coating, and examples of the method of applying pressure include the methods described in JP-T-2003-500857 ("IP-I" means searched and published International patent publication) and the like.

Examples of the light irradiation method include the methods described in JP-A-2001- 357S96 and the like. Examples of the methods utilizing plasma, microwaves or electric current include the methods described in JP-A-2002-353453 and the like. Examples of the chemical treatment include the methods described in JP-A-200l -357896 and the like.

f0llO} The method of coating the semiconductor fine particles on the electrically conductive support is included in the above-described method, such as a method of applying a semiconductor fine particle dispersion liquid on an electrically conductive support; and a method of applying a precursor of the semiconductor fine particles on an electrically conductive support, hydrolyzing the precursor under the action of the moisture in air, and thereby obtaining a semiconductor fine particle film, as described in Japanese Patent No. 2664194.

Examples of the precursor include (Nl-14),TiF6, titanium peroxide, a metal alkoxide, a metal complex and an organic acid metal salt.

Examples thereof include a method of applying a slurry additionally containing a metal organic oxide (alkoxide or the like), and forming a semiconductor film by a heating treatment, a light treatment or the like; and a method of charactcrizing the pH of the slurry additionally containing an inorganic precursor, and the slurry, and the properties and state of the dispersed titania particles. These slulTies may be added with a small amount of binder. Examples of the binder include celluloses, fluoropolymers, a crossl inked rubber, polyhutyl titanate, and carhoxymethyleellulose.

Examples of the tecimique related to the formation of a layer of semiconductor fine particles or a precursor layer thereof include a method of hydrophilizing the layer by a physical method using corona discharge, piasnia, LIV or the like; a chemical treaunent based on an alkali or on polyethylene dioxythiophene and polystyrenesulfonic acid or the like; formation of an intermediate film for bonding of polyaniline or the like.

{Ol1l} As the method of coating semiconductor fine particles on an electrically conductive support, (2) dry methods or (3) other niethods may he used together with the (1) wet methods described above. Preferred examples of the (2) dry methods include the methods described in JP-A-2000-23 1943 and the like. Preferred examples of the (3) other methods include the methods described in JP-A-2002-l34435 and the like.

tOl 12} Examples of the dry' method include deposition, sputtering, an aerosol deposition method, and the like. Furthermore, the eleetrophoresis method and the clcctrocrystallization method may also be uscd.

Furthermore, a method of first preparing a coating film on a heat resistant base, and then transferring the film to a film made of plastic or the like, may be used.

Preferabty, a method of transferring a layer through EVA as described in JP-A-2002- 184475; a method of forming a semiconductor layer and a conductive layer on a sacrificing base containing an inorganic salt that can he removed by ultraviolet rays or a water-based sotvent, subsequently transferring the layers to an organic base, and removing the sacrificing base as described in JP-A-2003-98977; and the like may be used.

fOll3} It is preferable for the semiconductor fine particles to have a large surface area, so that a large amount of dye can adsorb to the surface. For example, while the semiconductor finc particles have been coated on the support, the surface area is preferably 10 times or more, and more preferably 100 times or more, relative to the projected surface area. The upper limit of this value is not particularly limited, but the upper limit is usually about 5000 times. Preferred examples of the structure of the semiconductor fine particles include the structures disclosed in JP-A-200l -93591 and the like.

{Ol l4J In general, as the thickness of the semiconductor fine particle tayer increases, the amount of dye that can he supported per unit area increases, and therefore, the light absorption efficiency is increased. However, since the diffusion distance of generated elecbons increases along, the loss due to charge recombination is also increased.

Although a prefentd thickness of the semiconductor fine particle layer may vary with the utility of the element, the thickness is typically 0.1 to 100 pm. In the case of using it in the photoelectric conversion element for a photoelectrochemical cell, Ge thickness of the semiconductor finc particle lay-cr is preferably 1 to 50 p.m. and more prcferahly 3 to pm. The semiconductor fine particles may be calcined afier being applied on the support, at a temperature of 1 00 to 800°C for 1 0 minutes to 10 hours, so as to bring about cohesion of the particles. When a glass support is used, the film forming temperature is prefei.ahly 400 to 600°C.

When a polymer material is used as thc support, it is preferable that the formed film is heated at 250°C or less. The method of forming a film in this case may be any of (I) a wet method, (2) a dry method, and (3) an electrophoresis method (including an electrocrystallization method); preferably (1) a wet method or (2) a dry method; and further preferably (1) a wet method.

The amount of coating of the semiconductor fine particles per square meter of the support is preferably 0.5 to 500g. and more preferably 5 to 100g.

(F) Photoconductor layer When a dye is adsorbed onto the semiconductor fine particle layer produced as described above, a photoeondLlctor layer can be formed.

In order to adsorb the dye onto the semiconductor fine particles, well-dried semiconductor fine particles are preferably immersed into a dye solution for dye adsorption formed of a solvent and the dye for a long time. In regard to the solvent that is used in the dye solution for dye adsorption, any solvent capable of dissolving the dye for use in the present invention can be used without any particular limitation. For example, ethanol. methanol, isopropanol. toluene, t-hutanol, acetonitrile, acetone or n-butanol can be LLsed. Among them, ethanol and toluene can be preferably LLsed.

The dye solution for dye adsorption fonned from a solvent and the dye may be heated if necessary, at 50°C to 100°C. Adsorption of the dye may be carried out before or after the process of applying the semiconductor fine particles. Adsorption of the dye may also he conducted by simultaneously applying the semiconductor fine particles and the dye. Any unadsorbed dye is removed by washing. In the case of performing calcination of the coating film, it is preferable to ean'y out the adsorption of the dye after calcination. After calcination has been performed, it is particularly preferable to perform the adsorption of the dye rapidly before water adsorbs 10 the surface of the coating film. The dyes are selected so that tile wavelength region for photoelectric conversion can be rnadc as broad as possible when the dyes arc mixcd In the case of using a mixture of dyes, it is preferable to prepare a dye solution fbr dye adsorption by dissolving all of the dyes used therein.

WI 16} the overall amount of use of the dye is preferably 0.01 to 100 miilimoles, more preferably 0.1 to 50 millimoles, and particularly preferably 0.1 to 10 millimoles, per square meter of the support. In this case, the amount of use of the dye is preferably adjusted to 5% by mote or more.

The amount of the dye adsorbed to the semiconductor fine particles is preferably 0.001 to I millimole, and more preferably 0.1 to 0.5 millimole... based on I g of the semiconductor fine particles. When the amount of the dye is adjusted to such a range, the sensitization effect for the semiconductor can be sufficiently obtained.

For the purpose of reducing the interaction between dye molecules such as association, a colorless compound may be co-adsorbed. Examples of the hydrophobic compound that is co-adsorbed include steroid compounds having a carboxyl group (for cxaniplc, cholic acid and pivaloyl acid).

After the dye has been adsorbed, the surface of the semiconductor fine particles may be Ireated Lsmg amines. Preferred examples of the amines include 4-ten-butylpyridine, and polyvinylpyridine. These may he used directly when the compounds arc liquids, or may he used in a state of being dissolved in an organic solvent. {0il8

(C) Counter electrode the counter electrode is an etectrode working as a positive electrode in the photoelectrochemical cell. The counter electrode usually has the same meaning as the electrically conductive support described above, hut in a construction which is likely to maintain a sufficient strength, a support is not necessarily required. However, a construction having a support is advantageous in terms of sealability. Examples of the material ffir the counter electrode include platinum, carbon, and electrically conductive polymers. PrefelTed examples include platinum, carbon, and elecirically conductive polymers.

fOl l9} A preferred structure of the counter electrode is a structure having a high charge collecting effect. Preferred examples thereof include those described in JP-T- 10-505192 and the like.

In regard to the light-receiving electrode, a composite electrode of titanium oxide and tin oxide (Ti02/Sn02) or the like may be used. Examples of niixed electrodes of titania include those described in JP-A-2000-l 13913 and the like. Examples of mixed electrodes of materials other than titania include those described in JP-A-2001- 185243, JP-A-2003-282164 and the like.

{0 I 20} (H) Constitution of photoelectric conversion element As a constitution of the photoelectric conversion element, an eclectically conductive support (electrode layer), a photoelectric conversion layer (a photoeonductor layer and a charge transfer layer) a hole transport layer, a conductive layer, and a counter electrode layer can be sequentially laminated. A hole transport material functioning as a p-type semiconductor can also he used as the hole transport layer. For the hole transport layer, for example, an inorganic or an organic hole transport material can be used. Examples of the inorganic hole transport material include CuT, CuO. NiO and the like. Moreover, specific examples of the organic hole transport material include a polymer material and a low-molecular-weight material. Examples of the polymer material include polyvinyl carhazole. polyarnine, organic polysilane and the like.

Examples of the low-molecular-weight material include triphenylamine derivatives, stilbene derivatives, hydrazone derivatives, phenarnine derivatives and the like. Among these, an organic polysilane is preferable since it is different from conventional carbon polymers, and a polymer having a Si main chain and 6 electrons delocalized along the main chain contribute to the photoconduction, so that high hole mobility is exhibited (Phys. Rev. B. 1987, vol. 35. p. 2818).

The conductive layer is not particularly limited as long as it is highly conductive. Examples thereof include one formed of an inorganic conductive material, an organic conductive material, a conductive polymer, an intemmolecular charge-transfer complex or the like. Among them, the intermolecular charge-transfer complex composed of a donor material and an acceptor material is preferable. Among these. oiie formed of an organic donor and an organic acceptor is preferably used. The donor material is preferably rich in electrons in a molecular structure thereof. Examples thereof fficlude an organic donor material, such as a substance having a substituted or non-substituted amine group, a hydroxyl group, an ether group, a selen atom or a sulfur atom in it electrons of its molecule. More specifically, phenylamine-series materials, triphenylmethane-series materials. carbazole-series materials, phenol-series materials and tetrathiafulvalene-series materials can be exemplified. The acceptor material is preferably poor in electrons in a molecular structure thereof Examples thereof include fullerene, and an organic acceptor material, such as a substance having a substiftient, e.g. a nitro group, a cyano group, a carhoxyl group or a halogen group, in it electrons of its molecule. More specifically, PCBM; quinone-series materials such as henzoquinone-series materials, naphthoquinonc-serics materials and the like; fluorenonc-serics malerials; chloranils-series materials; bromanil-series materials; tetracyanoquinodimetliane-series materials; tetraeyanoneethylene-series materials; and the like can he exemplified.

The thickness of the conductive layer is not particularly limited, but a thickness with which the pores of the photovoltaic layer are entirely filled is preferable.

As a constitution of the clement, the element may have a structure formed by sequentially laminating a first electrode layer, a firsi photocondLietor layer, an electrically conductive layer, a second photoconductor layer, and a second electrode layer. In this case, the dyes used for the first photocondnctor layer and the second photoconductor layer may be identical or different. When the dyes are different, absorption spectra are preferably different. In addition thereto, a structure and a member that are applied to this kind of electrochemical element can he appropriately applied. (0123

The light-receiving electrode may be a tandem type electrode so as to increase the utility ratio of the incident light, or the like. Preferred examples of the tandem type construction include those described in JP-A-2000-90989, JP-A-2002-90989 and thc like.

The light-receiving electrode may he provided with the photo inanagemient function by which light scattering and reflection are efficiently achieved inside the light-receiving electrode layer. Preferred examples thereof include those described in JP-A-2002-93476 and the like.

It is preferable to form a short circuit preventing layer between the electrically conductive support and the photoconductor layer, so as to prevent reverse current due to a direct contact between the electrolyte liquid and the electrode. Preferred examples thereof include those described in JP-l'-6-507999 and the like.

It is preferable to employ a spacer or a separator so as to prevent the contact between the light-receiving electrode and the counter electrode. Preferred examples thereof include those described in JP-A-2001-283941 and the like.

{0l25} Methods for sealing a cell or a module preferably include a method using a polyisohutylcnc thcrrnosctting rcsin, a novolak resin, a photocuring (rnctli)acrylatc resin, an epoxy resin, an iononicr resin, glass frit, or alkoxidc for almnina and a method for laser fusing of low-melting point glass paste. When the glass frit is used, a mixture prepared by mixing powder glass with an acrylic resin being a binder may he used.

EXAMPLES

{0126J the present invention will be described in more detail based on examples given below, but the invention is not meant to be limited by these.

Synthesis Example 1 (Preparation of Exemplified Dye (X-26)) The exemplified dye (X-26) was prepared according to the method shown iii the following scheme. (OI28

1-heptyne Pd2(tII, a), PFh3 CuT Br S CHO NEt1, TI-IF d-l-1 d-1-2 CeH11flC5H1jfl C5H11nCH11n d-1-2

____ _____SS

LDA ms ThF 0 HO Toluene, reilax L L dh3 rixl7hr H -I

N N N N

d-1-4 d-1-S /! C5H11 T\ / F CO2H CO2H ci-Wu DMF,N2 F C5H11 d-l-7 ci / / CI / 160°Cx 3.5 hr 700Cx4br / C5H-pi / C5H11

________ A

(Hll \\ C:H 4NCS CN..a I -/ 130°Cx 6 hr,N>!'NCS HO2c / HOcflj N, C02H / / X-26 002H (0129} (i) Preparation of Compound (d-I-2) To mixed solution of 70 m L of triethyl amine and 50 m L of tetrahydrofuran (TI-IF), 25 g of Compound (d-1-1), 318 g ofPd(dba). 8.6 g oftriphenyl phosphine, 2.5 g of copper iodide, and 25.2 g of 1-heptyne were added. The resultant mixture was stirred at room temperature. and stirred at 80°C for 4.5 hours. After concentration, purification was performed by means of column chromatography, and thus 26,4 g of Compound (d-1 -2) was obtained.

(01 30( (ii) Preparation of Compound (d-I-4) tinder a nitrogen aunosphere at -15°C, 6.7 g of Compound (d-1-3) was dissolved in 200 nil, of terahydroftiran, and [DA (lithium diisopropylamide) that was separately prepared was added dropwise in an amount of 2.5 equivalents of Compound (d-1-3), and the resultant mixture was stirred for 75 minutes. Then, a solution in which 1 0 1 5 g of Compound (d-1 -2) was dissolved in 30 ml, of terahydroftiran was added dropwise, and the resultant mixture was stirred at 0°C for 1 hour, and stirred at room temperature for 17 hours. After concentration. 150 ni[. of water was added, and the resultant liquid was separated and extracted with 150 mL of methylene chloride, the resultant organic layer was washed with salt water. and the organic layer was concentrated. The crystal obtained was recrystallized with methanol, and then 18.9 g of Compound (d-1-4) was obtained.

(0131) (iii) Preparation of Compound (d-1-5) To 1,000 ml. of toluene, 13.2 g of Compound (d-1-4) and 1.7 g ofPPTS pyridinium para-toluenesulfonate) were added, and the resultant mixture was subjected to heating rellux for 5 hours under a nitrogen au osphere. Afier concentration, the resultant liquid was separated with a saturated aqueous solution of sodium hydrogencarhonate and nicthylcne chloride, and the resultant organic layer was concentrated. The crystal obtained was recrystallized with methanol and methylene chloride, and Gus 11.7 g of Compound (d-1-5) was obtained. 1324

(iv) Preparation of Exemplified Dye (X-26) To 60 mE of DMF (dimethylfomiamide). 4.0 g of Compound (d-l-5) and 2.2 g of Compound (d-1-6) were added, and the resultant mixture was stilTed at 70°C for 4 hours. Ihen, 2.1 g of Compound (d-1-7) was added, and the resultant mixture was stirred under heating at 160°( for 3.5 hours. Then, 19.0 g of ammonium thiocyanate was added, and the resultant mixture was stirred at I 30°C for S hours. After concentration, 1.3 mL of water was added, the resultant mixture was filtered, and the resultant cake was washed with diethyl ether. A crude purified product was dissolved in a methanol solution together with TBAOTT (tetrahutylammoniurn hydroxide) and purified by means of a Sephadex LI-1-20 column. A fraction in the main layer was recovered, and after concentration, a 0.2 M nitric acid solution was added, precipitates were filtered, washed with water and diethyl ether, and thus 600 tug of a crude purified product was obtained. The crude purified product was dissolved in a methanol solution, and 1 Ni of nitric acid was added, precipitates were filtered, and then washed with water and diethyl ether, and thus 570mg of the exemplified dye (X-26) was obtained.

f0133} The structure of the exemplified dye (X-26) obtained was confirmed by NMR measurement.

H-NMR (DMSO-d1. 400MHz): ö(ppm) in aromatic regions: c. 37 (1H. d). 9.11 (111, d), 9.04(1 H, s), 8.89 (2H), 8.74 (lI-I, s), 8.26 (H, d), 8.10-7.98 (21-fl, 7.85-7.73 (2H), 7.60 (1H, d), 7.45-7.33 (211). 7.33-7.12 (511, m), 6.92(111, d) When the exemplified dye (X-26) obtained was prepared to be 8.5 j.imol/T. in the dye concentration with ethanol solvent and spectral absorption measurement was carried oul, the absorption maximum wavelength was 568 urn.

{ 0135 Synthesis Example 2 ftrcparation of Exemplified Dye (X-30)) Compound (d-2-4) was prepared according to the method shown in the following scheme, and the exemplified dye (X-30) was prepared in a manner similar to the exemplified dye (X-26), except that the compound (d-1-2) was replaced with the compound (d-2-4).

{ 0136 BrMg0 -s -BuLi OF-IC d-2-i Pd2(db)3 [-Q'C5Hii f)kTh, 1IJ-D-"CSHll d-2-3 d-2-4 (0137) When the exemplified dye (X-30) obtained was prepared to he 8.5 jtmol/L in the dye concentration with ethanol solvent and spectral absorption measurement was carried out, the absorption maximum wavelength was 570 nrn.

{ 0138 Synthesis Example 3 (Preparation of Exemplified Dye (X-32)) Compound (d-3-2) was prepared according to the method shown in the following scheme, and the exemplified dye (X-32) was prepared in a manner similar to the exemplified dye (X-26), except that the compound (d-1-2) was replaced with the compound (d-3-2).

OHC TIN("C6H,> OHC J[-Br TSOH rflux d-3-1 d-3-2 When the excmplified dye (X-32) obtained was prepared to he 8S Rrnol/L in the dye concentration with ethanol solvent and spectral absorption measurement was canied out, the absorption maximum wavelength was 574 urn.

(0141} Synthesis Example 4 (Preparation of Exemplified Dye (X-3 1)) Compound (d-4-2) was prepared according to the method shown in Ihe following scheme, and the exemplified dye (X-3 1) was prepared in a manner similar to the exemplified dye (X-26). except that the compound (d-1-2) was replaced with the compound (d-4-2).

{0142J 1-ThT(CH), ONC S S Br TsDlJ s $ refl.px OF-ICj._zj#jN( C6H1)2 d-4-1 d-4-2 (0143 When Ihe exemplified dye (X-3 1) obtained was prepared to be 8.5 p.mol/L in the dye concentration with ethanol solvent and spectral absoiption measurement was carried out, the absorption maximum wavelength was 588 nrn. 0144}

Synthesis Example 5 (Preparation of Exemplified Dye (X-33)) Compound (d-5-6) was prepared according to the method shown in the following scheme, and thc exemplified dyc (X-33) was prcparcd in a manner similar to the exemplified dye (X-26), except that the compound (d-1-5) was replaced with the compound (d-5-6).

(0145)

TMS

TMS-K2003 Pd(PPh3)01, I / -t5H MH Gui, Et3M, TI-IF d-5-4 Br Br jC5H11 C5H11 s a

________ -

(0146) When Ihe exemplified dye (X-33) obtained was prepared lobe 8.5 Lmol/L in the dye concentration with ethanol solvent and spectral absorption measurement was carried out, the absorption maximum wavelength was 570 nm.

{0147( Synthesis Example 6 (Preparation of Exemplified Dye (X-34)) Compound (d-6-3) was prepared according to the method shown in the following scheme, and the exemplified dye X-34) was prepared in a manner similar to the exemplified dye (X-26). except that the compound (d-1-5) was replaced with the compound (d-6-3).

I-1\--Br "BuLi \=/ Br CISn(Bu)3 (rIBU)3sn8 d-S-2 THF d-6-1 d-6-2 BrN B EITh5__(IIs M: NKppp) d-6-2 t01491 When the exemplified dye (X-34) obtained was prepared to he 8.5 jtmol/L in the dye concentration with ethanol solvent and spectral absorption measurement was carried out, the absorption maximum wavelength was 571 mm Synthesis Example 7 (Preparation of Exemplified Dye (X-35)) The exemplified dyc (X-35) was prepared in a manner similar to the exemplified dye (X-30), except that the compound (d-2-2) was replaced with Ihe compound (d-7-1) described below.

(015I} \z:r/ Mg Br d-7-1 (0152} When Ihe exemplified dye (X-35) obtained was prepared Lobe 8.5 pniol/L in the dye concentration with ethanol solvent and spectral absorption measurement was carried out, the absorption maximum wavelength was 574mm {0153} Synthesis Example 8 (Preparation of Exemplified Dye (X-36)) The exemplified dye (X-36) was prepared in a manner similar to the exemplified dye (X-26) according to the method shown in the following scheme. t0154

"C5H11 cci,i3 CcHii'., -c, a NH4SCN c5Hl1nc&HtIcz:E.I::::H Ru-CI ---HOC-l6rcxa.s hr l3lrcxs hr dt6 CSHI1r?

I X-36

tO 155) When the exemplified dye (X-36) obtained was prepared to he 8.5 j.tmol/L in the dye concentration with ethanol solvent and spectral absorption measurement was carried out, the absorption maximum wavelength was 580mm {0156} The exemplified dye (X-22). the exemplified dye (X-23), the exemplified dye (X-24), the exemplified dye (X-25), the exemplified dye (X-27), and the exemplified dye (X-28) were also prepared in a similar maimer.

Moreover. the following dyes (X-19), (X-20) arid (X-2 1) were also prepared as comparative dyes with reference to the method described in 1. Am. Chem. Soc., 2001, vol. 123, p. 1613-1624.

{ 0157) 002H CO2MBu4 HO2C J HO2C* t*r'w' LLNh.:NCS NOS HO2C JZA%QJ II 02C CO2H CO2NBu4 X-19 X-20 [au:::çcs] cc2N6u4 X-21 tOl 59} <cEvaluation of Dyes> Ihe maximum absorption wavelengths of the above-described dyes (X-19) to (X-36) were measured. The results are shown in lable 1. The measurement was conducted using a spectrophotometer U-4100 (trade name, manufactured by hitachi High-Technologies Corp.). A solution was adjusted to have a concentration of 2 RM using T1-IF:ethanol = 1:1.

{0160}

Table I

Dye No. Maximum absorption wavelength (nrn) X-19 534 X-20 518 X-21 605 X-22 545 X-23 540 X-24 528 X-25 533 X-26 568 X-27 545 X-28 550 X-30 570 X-31 588 X-32 574 X-33 570 X-34 571 X-35 574 X-36 580 (0161} c:Preparation of dispersion liquid of semiconductor fine particles (II) locally having two or more kinds of metals or metallic compounds> Semiconductor fine particles (I) were prepared and, using the same, semiconductor fine particles (11) locally having two or more kinds of metals or metallic compounds were prepared.

-Preparation of semiconductor fine particles (I) (1) Tin oxide (Sn02) Puratronic (trade name) manuthctured by Alfa Aesar Company was used without purification. When a particle diameter of the tin oxide was measured using a laser diffraction-type particle diameter distribution analyzer (Mastersizer (trade name), manufactured by Malvern Instruments Ltd.). the particle diameter was 20 to 30 urn.

(2) litanium oxide (1102) Acetic acid (0.2 mol) was added dropwise to titanium isopropoxide (0.2 mol) at room temperature, and the resultant mixture was stirred for 15 minutes. Then, 290 mL of distilled water was added, and the resultant mixture was stirred for 1 hour. After I hour, a 65% HNO3 aqueous solution was added, the resultant mixture was heated to 78°C over 40 minutes, and stilTed for 75 minutes. Afler stirring, 290 mL of distilled water was added, and thus a titanium oxide sol solution (crystal system: amorphous) was produced. When the titanium oxide sol solution was stilTed at 250°C for 12 hours using an autoclave, an aqueous solution dispersed with titanium oxide particles was obtained.

Titanium oxide was obtained by filtering the aqueous solution. The crystal system of titanium oxide obtained was an anatase type. When a particle diarneler of the tin oxide was measured using a laser diffraction-type particle diameter distribution analyzer (Mastcrsizcr (trade name), manufactured by Malvem Instruments Ltd.), the particle diameter was 10 to 30 nm. {0l62

2. Preparation of semiconductor fine particles (II) locally having two or more kinds of metals or metallic compounds (1) Preparation of core-shell semiconductor fine particles (a) Preparation of semiconductor fine particles (II) having aluminum oxide (A1203) as a shell part The semiconductor fine particles (II) were dispersed into 2 to 150mM of trimethylaluminum aqueous solution, allowed to react for 8 seconds under a 200°C atmosphere, and thus semiconductor fine particles (11) were obtained. When the semiconductor fine particles obtained were observed by means of a transmission electron microscope (TEM), the semiconductor tine particles (IT) were thund to have a core-shell siruclure in which tin oxide or titanium oxide was contained as a core part, and aluminum oxide was contained as a shell part. When a volume ratio of core:shell was observed by means of TEM, the volume was from 90:10 to 98:2. When a particle diameter of the obtained semiconductor fine particles was measured using a laser diffraction-type particle diameter distribution analyzer (Mastersizer (trade name), manufactured by Malvern Instruments I td.), the particle diameter was 20 to 30 nm.

(0 163} (b) Preparation of semiconductor fine particles (II) having niagnesiuni oxide (MgO) as a shell part the semiconductor fine particles (1) were immersed for 1 minute into an ethanol solution (60 to 70°C) into which 2 to 150 mJvl of magnesium acetate was dissolved, and the resultant fine particles were washed and then ealeined at 500°C, and thus semiconductor fine particles (11) were obtained. When the semiconductor fine particles obtained were observed by means of a transmission electron microscope (TFM), semiconductor fine particles (IT) were found to have a core-shell structure in which tin oxide or titanium oxide was contained as a core part, and magnesium oxide was contained as a shell part. When a volume ratio of core:shell was observed by means of TEM in a similar manner as described above, the volume ratio was from 90:10 to 98:2. Whcn a particle diameter of the semiconductor fine particles was measured in a sinular manner as described above, the particle diameter was 20 to 30 nm.

{0164( (c) Preparation of semiconductor fine particles (II) having titanium oxide (Tb2) as a shell part The semiconductor fine parlicles (1) were immersed for 1 hour mb an TiC14 solution (70°C) of from 2 to 20 mM. and the resultant fine particles were washed and then calcined at 500°C, and thus semiconductor fine particles (II) were obtained. When the semiconductor fine particles obtained were observed by means of a transmission electron microscope (TEM), semiconductor fine particles (II) were found to have a core-shell structure in which tin oxide or titanium oxide was contained as a core part, and titanium oxide was contained as a shell part. When a volume ratio of core:shell was observed by nieans of TEM in a similar manner as described above, the volume ratio was from 90:10 to 98:2. When a particle diameter of the semiconductor line particles was measured in a similar manner as described above, the particle diameter was 20 to nrn.

tOl 65} (d) Preparatioti of semiconductor fine particles (II) having calcium carbonate (CaCO) asashellpart the semiconductor fine particles (1) werc immersed for a predetermined period of tinie into an aqueous solution of I to 3% by mass of calcium acetate, and the resultant fine particles were calcined at 525°C. and thus semiconductor fine particles (11) were obtained. When the semiconductor fme particles obtained were observed by means of a transmission electron microscope (TEM), semiconductor fine particles (II) were found to have a core-shell structure in which tin oxide or titanium oxide was contained as a core part, and calcium carbonate was contained as a shell part. When a volume ratio of core:shell was observed by means of TEM in a similar manner as described above, the volume ratio was from 90:10 to 98:2. When a particle diameter of the semiconductor fine particles was measured in a similar manner as described above, the particle diameter was 20 to 30 nm.

(e) Preparation of semiconductor tine particles (IT) having two or more kinds of materials as a shell part Semiconductor line particles having two or more kinds of materials as a shell pail were prepared by repeating the methods described in (a) to (d). When the semiconductor fine particles obtained were observed by means of a transmission electron microscope (TEM), semiconductor fine particles (11) are found to have a core-shell structure in which two or more kinds of materials used were contained as a shell part relative to a core part. When a volume ratio of core:shell was observed by means of TEM in a similar manner as described above, the volume ratio was from 90:10 to 98:1 When a particle diameter of the semiconductor fine particles was measured in a similar manner as described above, the particle diameter was 20 to 40 nm.

{01 67} (1) Addition of electrically conductive material Graphene was used as an electrically conductive material. Graphene was prepared by the following methods from flake graphite (average particle diameter: 4 pm, purity 99.95%, Qingdao (trade name) manufacturcd by Qingdao Tianhc Graphite Co, Ltd. (People's Republic of China)).

First, 5 g of graphite described above and 3.75 g of NaNO3 were added to a flask, 375 nil, of H2S04 was added, and the resultant mixture was stirred under ice cooling. Then, 22.5 g of KMnO4 was added over about 1 hour. The resultant mixture was stilTed for 2 hours under ice cooling, and then stirred for five days at room temperature. Then. 700 mL of aS wt% sulfuric acid aqueous solution was added, and the resultant mixture was stirred for 1 hour at a temperature maintained at 98°C. The mixture obtained was further stirred at 98°C for 2 hours. After a temperature was decreased to 60°C. 15 mL of a hydrogen peroxide aqueous solution was added, and the resultant mixture was stirred at room temperature for 2 hours. In order to remove impurity ions, the mixture obtained was purified by performing the following operations times.

(Purification method) Centrifugal separation was performed to remove a supemalanl. Then, 2 L of mixed aqueous solution of 3 w/o H2S04/0.5 wt3⁄4 W02 was added, and the resultant mixture was subjected to ultrasonication for 30 minutes while strongly' stirring the mixture, Then, the resultant mixture was washed three times with 2 L of 3 wt% MCI aqueous solution, and once wilh distilled waler. The aqueous solution obtained was purified by allowing the solution to pass through an ion exchange resin (D3OIT, Nankai University Chemical Plant).

When purification was perfonned by the meihod described above and distilled water was removed, grapheme was obtained. The purified substance was confirmed to be graphene according to X-ray photoelectron spectroseopy and by means of a scanning electron microscope. A material in which graphene was added to the semiconductor fine particles was prepared by compounding 1% by mass based on the semiconductor fine particles.

{01 68} (2) Preparation of metal -doped semiconductor tine particles TiLanium oxide semiconductor fine particles doped with Nb were produced by the following method.

A precursor was prepared by adding Nb powder (0002 mol) and tetrabutyl titanate (0.018 mol) to a 11202/N113 mixed solution (v/v = 5/1), and stirring the resultant mixture. The precursor was heated to 80°C to remove excess H702 and NH3, and then heated at 180°C for 20 hours using an autoclave. l'he dispersion obtained was washed with dcionizcd watcr having pH = 7 or less, and thc rcsultant material was dried at 100°C for 6 hours, to obtain Nb-doped titanium oxide semiconductor fine particles. The semiconductor fine particles being doped with Nb was confirmed by XRD or STEM.

When a particle diameter of the semiconductor fine particles was measured in a manner as described above, the particle diameter was 10 to 30 nm.

{0 I 69} 3. Preparation of dispersion liquid of semiconductor fine particle (11) The semiconductor fine particles (II) were dispersed into an a-terpineol solution containing 5% by mass of ethyl cellulose, and thus a dispersion liquid containing 15% by mass of the semiconductor fine particles (II) was obtained. The dispersion liquid was unifoimly dispersed and mixed using a mixing conditioner of rotation/revolution combination type.

(01 70} 4. Preparation of other semiconductor fine particle dispersion liquids In Comparative Examples 50 to 105 shown in the following tables, mixtures of two kinds of fine particles I and fine particles 2 in a mass ratio of] : I shown in the following tables were uscd. Herein, among the fine particles 2 shown in the following tables, "Ti02/MgO" represents fine particles prepared by immersing lift fine particles for 1 minute into an ethanol solution (60 to 70°C) into which 2 to 150 mM of magnesium acetate was dissolved, and the resultant fine particles were washed, and then calcined at 500°C.

<Evaluation of adsorption property> On a glass substrate, as a transparent electrically conductive film, fluorine-doped tin oxide was tornied by sputtering. Next, the seniiconductor fine particle dispersion liquid described above was applied to the transparent electrically conductive film and heated at 500°C. and thus a semiconductor fine particle layer was formed. A thickness of the semiconductor fine particle layer thus obtained was 10 mi, and an application amount of the semiconductor fine particles was 20 g/m2.

The glass substrate with the semiconductor fine particle layer formed thereon was immersed into a 10% ethanol solution of a dye shown in the following tables at 40°C for 3 hours in a dark place. Thc dye was dcsorbed using a 10% TBAOH methanol solution from a light-receiving electrode obtained by adsorption of the dye, and an amount of initial adsorption of each dye was quantitatively determined by measuring an absorption spectrum. One having the amount of adsorption of less than 2.0 x lo-mM/cm was rated as "B", and one having the amount of 2.0 x l0 mM/cm or more was rated as "A".

tO 172} <Evaluation of photoelectric conversion efficiency> (Production of photoelectric conversion element) A light-receiving electrode was produced in a manner similar to the method for evalLiating the adsorption properly described above. Then, the same semiconductor fine particle dispersion liquid was applied to this light-receiving electrode and heated at 500°C, and thus an insulating porous body was formed. Next, the glass substrate having the insulating porous body formed thereon was immersed for 12 hours in a 10% ethanol solution of each of the dyes indicated in the following Tables 2 to 9. The glass dyed with the dye was immersed for 30 minutes in a 10% ethanol solution of4-tert-hutylpyridine. and then the glass was washed with ethanol and naturally dried. The photoconductor layer thus obtained had a thickness of 10 tim, and the application amount of the semiconductor fine particles was 20 gun2.

Then. the senuconductor fine particle electrode was arranged, through a 50 micrometer-thick thennoplastic potyolefin resin sheet, on a position opposite to a platinum-sputtered FTO substrate, a resin sheet part was thermally fused, and thus both electrode plates were fixed.

Herein, an electrolytic liquid was injected from an electrolytic liquid injection port opened heffirehand on a side of the platinum sputter electrode, and a space between the electrodes was filled. Further, a peripheral part and the electrolytic liquid injection port were finniv sealed using an epoxy sealing resin, silver paste was applied to a currcnt collecting terminal section, and thus a photoelectric conversion clement was formed.

For the electrolytic liquid, a methoxypropionitrile solution of dimethylpropylimidazolium iodide (0.5 mol/I.) and iodine (0.1 mol/l) was used.

f0l73} (Measurement of photoelectric conversion efficiency) Pseudo-sunlight which did not include ultraviolet radiation was generated by passing the light of a 500-W xenon lamp (marnifactured by Llshio. Inc.) through an AM1.SG filter (manufactured by Oriel Instruments Corp.) and a sharp cutoff filter (Kenko L-42, trade name). The intensity of this light was 89mW/cm2. The produced photoelectric conversion element was irradiated with this light, and the electricity thus generated was measured with a current-voltage measurement device (Keithley-238 type, trade name). The results of measuring the initial value of the conversion efficiency of the photoclectrochemical cell thus determined arc shown in Tables 2 to 9. The results were evaluated such that one having a conversion efficiency of 4% or more and less than 5% was rated as "F"; one having a conversion efficiency of 5% or more and less than 6% \vas rated as "D"; one having a conversion efficiency of 6% or more and less than 7% was rated as "C"; one having a conversion efficiency of 7% or more and less than 8% was rated as "B"; and one having a conversion efficiency of 8% or more and less than 9% was rated as "A". One having a conversion efficiency rated as "A", "B" or "C" was deemed to he passable. Moreover, as durability, based on the initial value of the conversion efficiency, one having a conversion efficiency of 90% or more after 500 hours was rated as "A"; one having a conversion efficiency of 80% or more and less than 90% after 500 hours was rated as "B"; and one having a conversion efficiency of less than 80% after 500 hours was rated as "C". One rated as "A" or "B" was deemed to he passahle { 0174}

Table 2

Particles Dope Adsorption Conversion Dye Additive Durability -1 compoLind amount efficiency ______________ Exi X-22 hO2 Nb -B B B Ex2 X-22 TiO V -B C B Ex3 X-22 TiO, Ta -B C B Ex 4 X-22 hi02 Nb Graphene B B B Ex 5 X-22 bi02 Ta Graphene B B B Ex6 X-25 Ti01 Nb -B A A Ex7 X-25 TiO-, V -B B A ExS X-25 TiO, Ta -B B A Lx 9 X-25 fiO2 Nb Graphene B A A Ex 10 X-25 Ti02 V Graphene B A A Lxii X-27 Ti02 Nb -B B A Ex12 X-27 TiO V -B B A Ex13 X-27 TiO-, Ta -B B A Ex 14 X-27 Ti02 Nb Graphene B B A Lx 15 X-27 1102 V Graplienc B B A Ex16 X-22 Sn02 Nb -B C B Ex17 X-22 SnO-, V -B C B ExiS X-22 SnO-, Ta -B C B Ex 19 X-22 Sn02 Nb Graphene B B B Ex 20 X-22 Sn02 V Graphene B B B Ex21 X-25 SnO-Nb -B B A Ex22 X-25 Sn0 V -B C A Ex23 X-25 SilO2 Ta -B C A Ex 24 X-25 Sn02 Nb Graphene B B A Ex 25 X-25 Sn02 V Graphene B B A Ex26 X-27 5n02 Nb -B B A Ex27 X-27 Sn02 V -B C A Ex25 X-27 Sn02 Ta -B C A Ex 29 X-27 Sn02 Nb Graphene B B A Ex 30 X-27 Sn02 V Graphene B B A Ex31 X-30 Ti02 Nb -B B A Ex32 X-30 TiO V -B B A Ex33 X-30 Ti0 Ta -B B A Lx 34 X-30 1102 Nb Graphenc B A A Ex 35 X-30 Ti01 V (iraphene B A A Ex36 X-30 Sn02 Nb -B B A Ex 37 X-30 Sn02 V -B B A Ex38 X-30 Sn02 Ta -B B A Ex 39 X-30 Sn02 Nb Graphcne B B A Ex 40 X-30 Sn02 V Graphcnc B B A Lx means Example according to this invenUon.

1: Semiconductor tine particles -[01 75} Table 3 _____ _______ ________ ________ ________ _________ ________ Particles Dope Adsorption Conversion Dye * Additive Durability I compound amount etticiency Ex41 X-31 hO2 Nb -B A A Ex42 X-31 hi02 V -B B A Ex43 X-31 hO2 Ta -B B A Ex 44 X-31 Tb2 Nb Graphene B A A Ex 45 X-3 1 1102 V Grapliene B A A Ex46 X-31 Sn09 Nb -B A A Ex47 X-31 SnO V -B B A Ex4S X-31 Sn09 Ta -B B A Ex 49 X-3 1 Sn02 Nb Graphene B A A Ex 50 X-3 1 Sn02 V Graphene B A A Ex51 X-34 hO, Nb -B B B Ex52 X-34 Ti01 V -B B B Ex53 X-34 Ti01 Ta -B B B Ex 54 X-34 Ti02 Nb Graphene B A B Ex 55 X-34 Ti0 V Graphene B B B Ex56 X-34 Sn09 Nb -B B B ExST X-34 SnO V -B B B Ex58 X-34 SnO' Ta -B B B Ex 59 X-34 SnO, Nb Graphene B B B Ex 50 X-34 Sn02 V Graphene B B B Ex61 X-35 Ti02 Nb -B A B Ex52 X-35 1i02 V -B B B Ex53 X-35 hO, Ta -B B B Ex 54 X-35 hO2 Nb Graphene B A B Ex 55 X-35 Ti02 V Graphene B B B Ex56 X-35 SnO, Nb -B A B Ex57 X-35 Sn02 V -B B B Ex68 X-35 SnO, Ta -B B B Ex 59 X-35 Sn02 Nb Graphene B B B Ex 70 X-35 SnO, V Graphene B B B means Exaiupe according to this invention.

* 1: Semiconductor tine particles -[01 76} Table 4 _____ _______ _________ ________ _________ __________ ________ Particles Dope --Adsorption Conversion Dye Additive Durability I compound amount etticiency ____________ CEx1 X-l9 Tb2 --B D C C Ex 2 X-19 1102 -Graphcnc B C C CEx3 X-l9 SnO, --B E C C Ex 4 X-19 Sn02 -Graphene B D C CBx5 X-19 1102 Nb -B C C CEx6 X-l9 1102 V -B C C CEx7 X-19 1102 Ta -B D C CExS X-20 1102 --B D C C Ex 9 X-20 hO2 -(iraphene B C C CFxl0 X-20 Sn02 --B F C C Ex II X-20 Sn02 -Uraphene B D C CEx 12 X-20 lift Nb -B C C C hx 13 X-20 1102 V -H C C C Ex 14 X-20 102 Ta -B D C CExl5 X-2l 1102 --B C C CEx 16 X-21 1 102 -Graphene B C C CEx17 X-21 Sn02 --B C C C Ex 18 X-21 Sn02 -Graphene B C C CEx19 X-21 1102 Nb -B C C C Ex 20 X-2 1 1 102 V -B C C CEx2I X-21 1102 Ta -B D C CEx22 X-25 1102 --B C C CEx23 X-25 1102 -Graphene B C C CEx24 X-25 SnO-, --B C C C Ex 25 X-25 Sn02 -Graphene B D C "C Ex' uleaus Comparative Example.

* I: Semiconductor tine particles -[01 77} Table 5 _____ ______________ ________ ________ _________ ________ Particles *1 Adsorption Conversion Dye Additive Dura bilitv Core Shell amount efficiency Ex71 X-23 Ti02 Al-fl1 -B C B Ex72 X-23 Ti02 MgO -B C B Ex 73 X-23 Ti02 CaCO3 -A B B Ex 74 X-23 Ti02 A1201 Grapherte B B B Ex 75 X-23 Ti02 MgO Graphene B B B Ex 76 X-23 Ti02 CaCO3 Graphene A A B Ex 77 X-23 SilO, Al2O--B C B Ex 78 X-23 Sn01 hO1 -B C B Ex 79 X-23 Sn02 Ti02/Mg() -B B B Ex80 X-23 Sn02 MgO -B C B Ex SI X-23 Sn02 CaCO3 -A B B fix 82 X-23 SnO, A]201 Grapliene B B B fix 83 X-23 SnO, MgO Grapheiie B B B fix 84 X-23 Sn02 CaCO3 Graphene A B B TTx8S X-24 TiO-, A]201 -B C B fix 86 X-24 hO2 MgO -B C B fix 87 X-24 hO1 CaCO3 -A B B Ex 88 X-24 Ti02 A1201 Grapliene B B B Ex 89 X-24 Ti02 MgO Graphene B B B Ex 90 X-24 Ti02 CaCO (iraphene A B B Ex 91 X-24 SaG, Al-fl1 -B C B Ex 92 X-24 SitU' Ti01 -B C B Ex 93 X-24 SitU, Ti01/MgO -B B B Ex94 X-24 SaG, MgO -B C B Ex 95 X-24 SaG, CaCO3 -A B B Ex 96 X-24 SrtO2 A1201 Grapherte B B B Ex 97 X-24 SaG, MgO Graphene B B B Ex 98 X-24 SaG, CaCO5 Graphene A B B Ex99 X-26 Ti02 Ahth -B A A fix 100 X-26hi02 MgO -B B A fix 101 X-26 Ti02 CaCO1 -A A A fix 102 X-26 Ti02 A]201 Graphene B A A fix 103 X-26 Ti02 MgO Graphene B A A fix 104 X-26 Ti02 CaCO3 Graphene A A A fix 05 X-26 SnO, A]201 -B B A Ex 106 X-26 SaG, hit)1 -B C A fix 107 X-26 Sn02 Ti02/MgO -B B A fix 108 X-26 Sn02 MgO -B C A Ex 109 X-26 Sn02 CaCO3 -A B A fix 110 X-26 SW2 A1203 Graphene B B A fix 111 X-26 SW2 MgO Graphene B B A Ex 112 X-26 SW1 CaCO1 (iraphene A B A "fix" means Example according to this invention.

* 1: Semiconductor fine particles -[01 78} Table 6 _____ ________________ _________ __________ __________ _________ Particles *1 Adsorption Conversion Dye Additive. Dura bilitv Core Shell amount efficiency fixll3 X-28 Ti02 AL01 -B B A Ex 114 X-28 TiC)2 MgO -B C A Ex115 X-28 Ti02 CaCth -A B A Ex 116 X-28 Ti02 Al2O Graphene B B A Ex 117 X-28 Ti02 MgO Graphene B B A Ex 118 X-28 Ti02 CaCO Graphene A A A Ex 119 X-28 SnO, 1\1201 -B B A Ex 120 X-28 SW1 TiC)1 -B C A fix 121 X-28 Sn02 Ti02!MgO -B B A fix 122 X-28 Sn02 MgO -B C A fix 123 X-28 Sn02 CaCO5 -A B A fix 124 X-28 SnO, A]2O Graphene B B A fix 125 X-28 SaC), MgO Grapliene B B A fix 126 X-28 Sn02 CaCO3 Graphene A B A Ex 127 X-32 TiC)2 Al2& -B A A Ex128 X-32 TiC)2 MgO -B B A fix 129 X-32 TiC)2 CaCO2 -A A A lix 130 X-32 Ti02 A1203 Grapliene B A A lix 131 X-32 Ti02 MgO Grapliene B A A lix 132 X-32 TiC)2 CaCO Graphene A A A fix 133 X-32 SaC), A12O -B B A lix 134 X-32 SW2 TiC)2 -B B A fix 135 X-32 Sn02 Ti01/MgO -B B A Ex 136 X-32 SnO MgO -B B A Ex 137 X-32 SnOn CaCO3 -A A A fix 138 X-32 SnO, A1203 Graphene B B A Ex 139 X-32 SaC)2 MgO Graphene B B A Ex 140 X-32 Sn02 CaCO Graphene A A A fix 141 X-33 TIC)1 A11O -B B B Ex 142 X-33 TiC)2 MgO -B B B Ex 143 X-33 Ti01 CaCO3 -A B B fix 144 X-33 TiC)I A]2O Graphene B B B Ex 145 X-33 TiC)2 MgO Graphene B B B fix 146 X-33 Ti02 CaCO1 Graphene A B B Ex 147 X-33 SaC), 1\l2C) -B B B Ex 148 X-33 SaC)1 TiC)1 -B B B fix 149 X-33 Sn02 Ti02/MgO -B B B fix 150 X-33 SaC), MgO -B B B Ex151 X-33 SnO CaCO5 -A B B fix 152 X-33 SnO, A1202 Graphene B B B Ex 153 X-33 SaC)2 MgO Graphene B B B lix 154 X-33 Sn0 CaCth Grapherie A B B fix' means Example according to this invention.

1: Senñconductor fine particles -[01 79} Table 7 ______ _____________________________ ___________ ____________ ___________ Particles *1 Adsorption Conversion Dye Additive Durability Core Shell amouat efliciency Ex155 X-36 TIC)9 AW1 -B B B Ex156 X-36 TiOl MgO -B B B Ex157 X-36 hO2 CaCO3 -A B B Ex 158 X-36 T102 A]203 Graphene B B B Ex 159 X-36 hO2 MgO Graphene B B B Ex 160 X-36 Ti02 CaCO.; Graphene A B B Ex 161 X-36 Sn02 A110, -B B B Ex 162 X36 SaC)9 TiO -B B B lix 163 X-36 Sn02 Ti02/Mg() -B B B Ex164 X-36 SnO MgO -B B B lix 165 X-36 SnOl CaCO6 -A B B lix 166 X-36 Sn02 A]1O Graphene B B B Ex 167 X-36 SW2 MgO Graphene B B B lix 168 X-36 Sn02 CaCO5 Graphene A B B CTh26 X-l9 TIC), --B D C C Lx 27 X-l9 Ti01 -Graphene B C C CLx28 X-l9 Sn09 --B E C C Ex 29 X-19 SnO -Graphene B D C CEx3O X-19 Ti01 A1'O; -B C C C Ex 3! X-!9 Ti01 Mg() -B D C CEx32 X-19 TIC)1 CaCO -A C C C Ex 33 X-!9 Ti01 A120; Graphene B C C C Ex 34 X-19 Ti01 MgO Graphene B C C C Ex 35 X-19 Ti02 CaCO3 Graphene A C C CEx36 X-20 Ti09 --B D C Clix 37 X-20 Tb2 -Graphene B C C CEx38 X-20 SiiO --B E C C Ex 39 X-20 Sn02 -Graphene B D C CEx4O X-20 Tb, A]10, -B C C CEx41 X-20 Ti02 MgI) -B D C CEx42 X-20 TiO CaCO; -A C C Clix 43 X-20 Ti01 A]2O Graphene B C C C lix 44 X-20 Ti01 MgO Graphene B C C C lix 45 X-20 Ti02 CaCO3 Graphene A C C Clix46 X-26 T109 --B C C C Ex 47 X-26 Ti02 -Graphene B C C CLx4S X-26 SaC), --B C C Clix 49 X-26 5n02 -Graphene B D C lix' means Examp'e according to this invention.

C Lx" means Comparative Example.

1: Semiconductor fine particles Table 8 ______ _______________________ __________ ___________ ____________ ___________ Particles * 1 -, Adsorption Conversion Dye Fine Fine Additive -Durability amount efficiency _________ ______ particles I particles 2 -C Dx 50 X-23 TiC)2 AbC)3 -B F C CEx5I X-23 TiC)2 MgO -B F C CExS2 X-23 TiC)2 CaCO3 -A D C C Dx 53 X-23 TiC)2 AbC)3 Graphene B D C C Dx 54 X-23 Ti02 MgO Graphene B D C C' Ex 55 X-23 TiC)2 C'aCO3 Graphcnc A C' C CEx56 X-23 SW2 AbC)3 -B C C C Ex 57 X-23 SW2 hO' -B C C C Ex 58 X-23 Sn02 TiOn/MgO -B D C CEx59 X-23 SW2 MgO -B F C C Ex 60 X-23 SW2 CaCO1 -A D C C Ex 61 X-23 Sn02 Al203 Graphene B D C C Ex 62 X-23 Sn02 MgO Graphene B D C C Ex 63 X-23 Sn02 CaCO3 Graphene A D C C Dx 64 X-24 TiC)2 AbC)3 -B E C CEx6S X-24 Ti02 MgO -B F C C Ex 66 X-24 TiC)2 CaCO3 -A D C CEx67 X-24 TiC)2 A1203 Graphene B D C C Ex 68 X-24 Ti02 MgO Graphene B U C C Ex 69 X-24 Ti02 CaCO3 Graphene A U C C Ex 70 X-24 SW2 Al203 -B F C CDx7I X-24 SW2 TiO -B F C C Ex 72 X-24 SW2 1 iC)2IMgO -B D C CDx73 X-24 SW2 MgC) -B F C Chx74 X-24 SW2 CaCC)3 -A D C C' Ex 75 X-24 Sn02 A1203 Graphcnc B D C C Dx 76 X-24 SW2 MgO Graphene B D C C Ex 77 X-24 SW2 CaCC)3 Graphcnc A U C "C lTx" means Comparative Example.

* I: Semiconductor fine particles Table 9 ______ _______________________ __________ ___________ ____________ __________ Particles *1 -, Adsorption Conversion Dye Fine Fine Additive -Durability amount efficiency ___________ _______ particles 1 particles 2 C Ex 78 X-26 Ti01 AM)3 -B C C CEx79 X-26 Ti0 MgO -B D C C.ExSO X-26 hO1 CaCO3 -A C C C Ex 8! X-26 TiOn A1203 (Iraphene B C C C Ex 82 X-26 Ti03 MgO Graphene B C C C Ex 83 X-26 1102 CaCO3 Graphene A C C CExS4 X-26 Sn0 A1,03 -B D C CExS5 X-26 Sn02 TiO, -B E C CExS6 X-26 Sn02 Ti02/MgO -B D C CExS7 X-26 Sn02 MgO -B 12 C CExSS X-26 Sn02 CaCO3 -A D C C Ex 89 X-26 Sn02 A1203 Graphene B D C C Ex 90 X-26 Sn02 MgO Graphene B D C C Ex 91 X-26 Sn02 CaCO3 Graphene A D C CEx92 X-28 Ti01 AM) -B D C CFx93 X-28 hO3 MgO -B F C CFx94 X-28 110 CaCO3 -A 1) C C Ex 95 X-28 hO3 A1203 Graphene B D C C lix 96 X-28 hO2 MgO Graphene B 1) C C lix 97 X-28 hO3 CaCO3 Graphene A C C CEx9S X-28 Sn0 A1,03 -B D C CEx99 X-28 Sn02 TiO -B E C Clix 100 X-28 Sn0 F i02/MgO -B U C CEx1OI X-28 Sn0 MgO -B E C ChxlO2 X-28 Sn01 CaCO3 -A U C Clix 103 X-28 Sn02 Al203 Graphenc B U C C Ex 104 X-28 SnO MgO Graphene B D C Clix 105 X-28 Sn03 CaCO3 Graphene A U C "C lix" means Comparative Example.

* 1: Semiconductor fine particles tOI82 As shown in Tables 4 and 7, it is found that in Comparative Examples ito 21 and 26 to 46, in which the dye represented by Foimula (1) was not used or the semiconductor fine particles were not composed of two or more kinds of metals or metallic compounds. the initial value of conversion efficiency was insufficient in many cases, and durability was not passable in any of cases. Moreover, fables B and 9 showed that either of the initial value of photoelectric conversion efficiency or durability was not passable for one obtained by merely mixing two kinds of semiconductor fine particles, and both were not passable for most of the ones.

In contrast, when the semiconductor frne particles locally having two or more kinds of metals or metallic compounds were used and the dye represented by Formula (1) was employed, the initial value of photoelecftic conversion efficiency and durability are found to be excellent. (0183

Having described our invention as related to the present embodiments, it is our intentioti that the invention not be limited by ally of the details of the description, unless otherwise specified, but rather be construed broadly within its spirit and scope as set out in the accompanying claims Ihis non-provisional application claims priority on Patent Application No. 2011-076724 filed in Japan on March 30, 2011, and Patent Application No. 2012- 052699 filed in Japan on March 9. 2012. each of which is entirely herein incorporated by reference.

REFERENCE SIGNS LIST

1 Electrically conductive support 2 Photoconductor layer 21 Sensitizing dye 22 Semiconductor fine particle 3 Charge transfer layer 4 Counter elecflode Light-recciving electrode 6 External circuit 10 Photoelectric conversion element Photoelectrochemical cell