JPH1176836A - Composite oxide thin film and its preparation - Google Patents
Composite oxide thin film and its preparationInfo
- Publication number
- JPH1176836A JPH1176836A JP10169398A JP16939898A JPH1176836A JP H1176836 A JPH1176836 A JP H1176836A JP 10169398 A JP10169398 A JP 10169398A JP 16939898 A JP16939898 A JP 16939898A JP H1176836 A JPH1176836 A JP H1176836A
- Authority
- JP
- Japan
- Prior art keywords
- thin film
- composite oxide
- oxide thin
- titanium
- oxide
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000010409 thin film Substances 0.000 title claims abstract description 44
- 239000002131 composite material Substances 0.000 title claims abstract description 35
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 claims abstract description 24
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 claims abstract description 21
- 229910052751 metal Inorganic materials 0.000 claims abstract description 9
- 239000002184 metal Substances 0.000 claims abstract description 9
- 229910044991 metal oxide Inorganic materials 0.000 claims abstract description 9
- 150000004706 metal oxides Chemical class 0.000 claims abstract description 9
- 238000010438 heat treatment Methods 0.000 claims abstract description 7
- 230000001699 photocatalysis Effects 0.000 claims abstract description 6
- 239000000203 mixture Substances 0.000 claims abstract description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 3
- 239000001301 oxygen Substances 0.000 claims abstract description 3
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 3
- 230000031700 light absorption Effects 0.000 claims description 16
- 229910010413 TiO 2 Inorganic materials 0.000 claims description 12
- 230000002070 germicidal effect Effects 0.000 claims description 10
- 239000013078 crystal Substances 0.000 claims description 9
- 238000000034 method Methods 0.000 claims description 9
- 239000000758 substrate Substances 0.000 claims description 9
- 230000007062 hydrolysis Effects 0.000 claims description 8
- 238000006460 hydrolysis reaction Methods 0.000 claims description 8
- 239000011941 photocatalyst Substances 0.000 claims description 6
- 239000010936 titanium Substances 0.000 claims description 6
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 5
- 239000003960 organic solvent Substances 0.000 claims description 5
- 229910052719 titanium Inorganic materials 0.000 claims description 5
- 150000003609 titanium compounds Chemical class 0.000 claims description 5
- 238000004519 manufacturing process Methods 0.000 claims description 4
- 108010025899 gelatin film Proteins 0.000 claims description 3
- 150000007522 mineralic acids Chemical class 0.000 claims description 3
- 150000007524 organic acids Chemical class 0.000 claims description 3
- 150000002739 metals Chemical class 0.000 claims 1
- 150000002902 organometallic compounds Chemical class 0.000 claims 1
- 238000010521 absorption reaction Methods 0.000 abstract description 16
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 abstract description 8
- 239000010408 film Substances 0.000 abstract description 8
- 230000001954 sterilising effect Effects 0.000 abstract description 2
- XOLBLPGZBRYERU-UHFFFAOYSA-N tin dioxide Chemical compound O=[Sn]=O XOLBLPGZBRYERU-UHFFFAOYSA-N 0.000 abstract 2
- 239000000243 solution Substances 0.000 description 17
- XNWFRZJHXBZDAG-UHFFFAOYSA-N 2-METHOXYETHANOL Chemical compound COCCO XNWFRZJHXBZDAG-UHFFFAOYSA-N 0.000 description 15
- VXUYXOFXAQZZMF-UHFFFAOYSA-N titanium(IV) isopropoxide Chemical compound CC(C)O[Ti](OC(C)C)(OC(C)C)OC(C)C VXUYXOFXAQZZMF-UHFFFAOYSA-N 0.000 description 11
- 238000000862 absorption spectrum Methods 0.000 description 9
- BCWYYHBWCZYDNB-UHFFFAOYSA-N propan-2-ol;zirconium Chemical compound [Zr].CC(C)O.CC(C)O.CC(C)O.CC(C)O BCWYYHBWCZYDNB-UHFFFAOYSA-N 0.000 description 9
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical group CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 description 8
- 238000002441 X-ray diffraction Methods 0.000 description 7
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 6
- 239000000126 substance Substances 0.000 description 5
- 230000000052 comparative effect Effects 0.000 description 4
- PMTRSEDNJGMXLN-UHFFFAOYSA-N titanium zirconium Chemical compound [Ti].[Zr] PMTRSEDNJGMXLN-UHFFFAOYSA-N 0.000 description 4
- 150000003755 zirconium compounds Chemical class 0.000 description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 description 3
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 description 3
- 230000001590 oxidative effect Effects 0.000 description 3
- 229910052726 zirconium Inorganic materials 0.000 description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 239000000356 contaminant Substances 0.000 description 2
- 238000000354 decomposition reaction Methods 0.000 description 2
- 238000007598 dipping method Methods 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- RVTZCBVAJQQJTK-UHFFFAOYSA-N oxygen(2-);zirconium(4+) Chemical compound [O-2].[O-2].[Zr+4] RVTZCBVAJQQJTK-UHFFFAOYSA-N 0.000 description 2
- 239000004065 semiconductor Substances 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 229910001928 zirconium oxide Inorganic materials 0.000 description 2
- 241000894006 Bacteria Species 0.000 description 1
- VCUFZILGIRCDQQ-KRWDZBQOSA-N N-[[(5S)-2-oxo-3-(2-oxo-3H-1,3-benzoxazol-6-yl)-1,3-oxazolidin-5-yl]methyl]-2-[[3-(trifluoromethoxy)phenyl]methylamino]pyrimidine-5-carboxamide Chemical compound O=C1O[C@H](CN1C1=CC2=C(NC(O2)=O)C=C1)CNC(=O)C=1C=NC(=NC=1)NCC1=CC(=CC=C1)OC(F)(F)F VCUFZILGIRCDQQ-KRWDZBQOSA-N 0.000 description 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
- 241000700605 Viruses Species 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 238000003915 air pollution Methods 0.000 description 1
- 244000052616 bacterial pathogen Species 0.000 description 1
- FPCJKVGGYOAWIZ-UHFFFAOYSA-N butan-1-ol;titanium Chemical compound [Ti].CCCCO.CCCCO.CCCCO.CCCCO FPCJKVGGYOAWIZ-UHFFFAOYSA-N 0.000 description 1
- WUKWITHWXAAZEY-UHFFFAOYSA-L calcium difluoride Chemical group [F-].[F-].[Ca+2] WUKWITHWXAAZEY-UHFFFAOYSA-L 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- RKTYLMNFRDHKIL-UHFFFAOYSA-N copper;5,10,15,20-tetraphenylporphyrin-22,24-diide Chemical compound [Cu+2].C1=CC(C(=C2C=CC([N-]2)=C(C=2C=CC=CC=2)C=2C=CC(N=2)=C(C=2C=CC=CC=2)C2=CC=C3[N-]2)C=2C=CC=CC=2)=NC1=C3C1=CC=CC=C1 RKTYLMNFRDHKIL-UHFFFAOYSA-N 0.000 description 1
- 238000007865 diluting Methods 0.000 description 1
- 238000003618 dip coating Methods 0.000 description 1
- XGZNHFPFJRZBBT-UHFFFAOYSA-N ethanol;titanium Chemical compound [Ti].CCO.CCO.CCO.CCO XGZNHFPFJRZBBT-UHFFFAOYSA-N 0.000 description 1
- 238000004817 gas chromatography Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 150000002736 metal compounds Chemical class 0.000 description 1
- ZEIWWVGGEOHESL-UHFFFAOYSA-N methanol;titanium Chemical compound [Ti].OC.OC.OC.OC ZEIWWVGGEOHESL-UHFFFAOYSA-N 0.000 description 1
- 229910017604 nitric acid Inorganic materials 0.000 description 1
- 239000000575 pesticide Substances 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 238000006748 scratching Methods 0.000 description 1
- 230000002393 scratching effect Effects 0.000 description 1
- 239000010865 sewage Substances 0.000 description 1
- 238000003900 soil pollution Methods 0.000 description 1
- 238000004528 spin coating Methods 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- 238000004659 sterilization and disinfection Methods 0.000 description 1
- 239000004094 surface-active agent Substances 0.000 description 1
- 238000011179 visual inspection Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、複合酸化物薄膜お
よびその製造法に関する。更に詳しくは、光触媒などと
して有効に用いられる複合酸化物薄膜およびその製造法
に関する。[0001] The present invention relates to a composite oxide thin film and a method for producing the same. More specifically, the present invention relates to a composite oxide thin film effectively used as a photocatalyst and the like and a method for producing the same.
【０００２】[0002]
【従来の技術】水質、大気、土壌汚染などの環境問題は
年々重要視されており、化学物質、特に有機溶媒、農
薬、界面活性剤等の汚染物質や人体に悪影響を及ぼすウ
ィルス、菌等の除去が望まれている。これらの汚染物質
や病原菌を除去するために、紫外光を用いたオゾン処理
法が多用されているが、処理後にオゾンが残存するた
め、更にこれを除去する技術を必要としている。2. Description of the Related Art Environmental problems such as water quality, air and soil pollution are becoming more and more important year by year, and contaminants such as chemicals, especially organic solvents, pesticides, surfactants, etc., and viruses and bacteria which adversely affect the human body are considered. Removal is desired. In order to remove these contaminants and pathogenic bacteria, an ozone treatment method using ultraviolet light is frequently used. However, since ozone remains after the treatment, a technique for further removing ozone is required.
【０００３】一方、TiO2、ZrO2、ZnO等の光触媒によっ
て化学物質を分解する方法は、薬品等を用いないためク
リーンであり、また太陽光などの光エネルギーの利用が
可能であるため、現在注目されている環境浄化方法であ
る。On the other hand, a method of decomposing a chemical substance by using a photocatalyst such as TiO 2 , ZrO 2 , ZnO is clean because it does not use chemicals or the like, and can use light energy such as sunlight. It is an environmental purification method that has attracted attention.
【０００４】光触媒による処理方法で使用される半導体
材料は、吸収端、即ち半導体を最も効率良く励起できる
光の波長を有している。特に、現在光触媒としてTiO2が
最も多用されているが、これの光触媒機能の発現には38
8nm以下の波長の光を照射することが必要であり、効率
良くTiO2を励起できる光源としては、一般にブラックラ
イト(中心波長368nm)を用いることが行われている。A semiconductor material used in a photocatalytic treatment method has an absorption edge, that is, a wavelength of light that can excite a semiconductor most efficiently. In particular, TiO 2 is most frequently used as a photocatalyst at present.
It is necessary to irradiate light having a wavelength of 8 nm or less, and black light (center wavelength: 368 nm) is generally used as a light source capable of efficiently exciting TiO 2 .
【０００５】一方、殺菌などに利用されている殺菌灯
(波長254nm)は、螢光灯を使用しているブラックライト
と比較して、エネルギー利用効率(ランプからの放出エ
ネルギー/ランプへの供給エネルギー)が高く、エネルギ
ーの有効活用を考慮した場合、殺菌灯を用いた処理シス
テムを構築することが望ましい。On the other hand, a germicidal lamp used for sterilization, etc.
(Wavelength 254 nm) has a higher energy use efficiency (emission energy from the lamp / energy supplied to the lamp) compared to black light using fluorescent lamps. It is desirable to build a processing system using lights.
【０００６】[0006]
【発明が解決しようとする課題】本発明の目的は、TiO2
やZrO2等の単体で観察される吸収端波長とは異なる波長
で強い吸収を示し、殺菌灯(波長254nm)の照射によって
光触媒活性を示す複合酸化物薄膜およびその製造法を提
供することにある。SUMMARY OF THE INVENTION An object of the present invention is to provide TiO 2
The present invention provides a composite oxide thin film that exhibits strong absorption at a wavelength different from the absorption edge wavelength observed with a simple substance such as ZrO 2 or ZrO 2 and exhibits photocatalytic activity by irradiation with a germicidal lamp (wavelength 254 nm) and a method for producing the same. .
【０００７】[0007]
【課題を解決するための手段】かかる本発明の目的は、
酸化チタンおよび禁制帯幅3.2eV以上の酸化チタン以外
の金属酸化物からなる複合酸化物薄膜によって達成さ
れ、かかる複合酸化物薄膜は、有機チタン化合物および
酸化物が3.2eV以上の禁制帯幅を有するチタン以外の金
属の有機金属化合物の混合物有機溶媒溶液に無機酸また
は有機酸を添加してチタンおよび他の金属を含有する加
水分解ゾルを形成させ、このゾルを基板上に塗布してゲ
ル膜を形成させた後、約300〜1200℃の温度で加熱処理
することによって製造される。SUMMARY OF THE INVENTION The object of the present invention is as follows.
This is achieved by a composite oxide thin film composed of titanium oxide and a metal oxide other than titanium oxide having a band gap of 3.2 eV or more, and the composite oxide thin film has an organic titanium compound and an oxide having a band gap of 3.2 eV or more. A mixture of an organic metal compound of a metal other than titanium, an inorganic acid or an organic acid is added to an organic solvent solution to form a hydrolysis sol containing titanium and another metal, and the sol is applied on a substrate to form a gel film. After being formed, it is manufactured by heat treatment at a temperature of about 300 to 1200 ° C.
【０００８】[0008]
【発明の実施の形態】酸化チタンおよび禁制帯幅3.2eV
以上の酸化チタン以外の金属酸化物からなる複合酸化物
薄膜は、一般式 (1-x)TiO2・xMOy で示され、ここでMOyは禁制帯幅3.2eV以上の酸化チタン
以外の金属酸化物であり、0.05≦x<1.00であり、yは金
属Mに対応する酸化物酸素数であり、0.1≦x≦0.9の場合
には、複合酸化物薄膜は無定形結晶構造を有する。BEST MODE FOR CARRYING OUT THE INVENTION Titanium oxide and forbidden band width 3.2 eV
Composite oxide thin film is represented by the general formula (1-x) TiO 2 · xMO y, where MO y is other than titanium oxide or bandgap 3.2eV metal made of a metal oxide other than titanium oxide or It is an oxide, 0.05 ≦ x <1.00, y is an oxide oxygen number corresponding to the metal M, and when 0.1 ≦ x ≦ 0.9, the composite oxide thin film has an amorphous crystal structure.
【０００９】上記一般式において、酸化チタンと共に禁
制帯幅が3.2eV以上の酸化チタン以外の金属酸化物が用
いられるとされるのは、酸化チタンの禁制帯幅である3.
2eV以下のものが用いられると、複合酸化物薄膜の光吸
収特性が変化して、光照射によって生じた電子と正孔が
反応に寄与する前に再結合し易くなり、反応効率で低下
するためであり、また禁制帯幅が狭くなるため、反応に
おける酸化力が低下することが懸念されるためである。
ここで、MOyとしては、例えばZrO2、SnO2、SiO 2等が用
いられ、好ましくはZrO2が用いられるので、以下では他
の金属としてジルコニウムを用いた態様について説明す
る。In the above general formula, titanium oxide is prohibited together with titanium oxide.
Uses metal oxides other than titanium oxide with a band width of 3.2 eV or more
It is said that the band gap of titanium oxide is said to be 3.
If a material with 2 eV or less is used, the light absorption of the composite oxide thin film
The absorption characteristics change, and electrons and holes generated by light irradiation
Easy to recombine before contributing to reaction, resulting in lower reaction efficiency
And the forbidden band becomes narrower,
This is because there is a concern that the oxidizing power in the catalyst may decrease.
Where MOyFor example, ZrOTwo, SnOTwo, SiO TwoEtc. are for
And preferably ZrOTwoIs used, so other
An embodiment using zirconium as the metal will be described.
You.
【００１０】チタンージルコニウム含有加水分解ゾル
は、有機チタン化合物および有機ジルコニウム化合物の
加水分解によって調製される。有機チタン化合物として
は、例えばテトラメトキシチタン、テトラエトキシチタ
ン、テトラn-プロポキシチタン、テトライソプロポキシ
チタン、テトラn-ブトキシチタン、テトライソブトキシ
チタン等が、また有機ジルコニウム化合物としては、こ
れらの有機チタン化合物に対応するジルコニウム化合物
が用いられる。The titanium-zirconium-containing hydrolysis sol is prepared by hydrolysis of an organic titanium compound and an organic zirconium compound. As the organic titanium compound, for example, tetramethoxytitanium, tetraethoxytitanium, tetra-n-propoxytitanium, tetraisopropoxytitanium, tetra-n-butoxytitanium, tetraisobutoxytitanium, etc., and as the organic zirconium compound, these organic titanium A zirconium compound corresponding to the compound is used.
【００１１】これらの有機チタン化合物および有機ジル
コニウム化合物とは、所定のモル比で、エチレングリコ
ールモノメチルエーテル等の有機溶媒に溶解または希釈
して用いられ、その溶液に塩酸、硝酸等の無機酸または
酢酸等の有機酸を上記有機溶媒溶液として加えることに
より、分子レベルで均一な、透明かつ安定な加水分解ゾ
ルを得ることができる。These organic titanium compounds and organic zirconium compounds are used by dissolving or diluting them in an organic solvent such as ethylene glycol monomethyl ether at a predetermined molar ratio, and the solution is mixed with an inorganic acid such as hydrochloric acid or nitric acid or acetic acid. By adding such an organic acid as a solution of the above-mentioned organic solvent, a uniform, transparent and stable hydrolysis sol at the molecular level can be obtained.
【００１２】得られたチタン-ジルコニウム含有加水分
解ゾルを用い、ディップコーティング法、スピンコーテ
ィング法、スプレー法等により、ガラス板等の基材上に
ゲル膜を形成させ、これを約300〜1200℃、好ましくは
約400〜700℃の温度で約10分間〜3時間程度加熱処理す
ると、チタン-ジルコニウム複合酸化物薄膜が得られ
る。Using the obtained titanium-zirconium-containing hydrolyzed sol, a gel film is formed on a substrate such as a glass plate by a dip coating method, a spin coating method, a spray method or the like. Heat treatment at a temperature of preferably about 400 to 700 ° C. for about 10 minutes to 3 hours gives a titanium-zirconium composite oxide thin film.
【００１３】前記一般式において、0.05≦x≦0.20と
し、その加熱処理温度を約600℃以下にすると、形成さ
れる複合酸化物薄膜と基材との間の付着性を向上させる
ことができ、これを光触媒として用いたとき互いに接触
する流動層を備えた汚水処理などに対して実用に耐える
膜強度を付与する。また、他の金属酸化物の混合割合が
低いことから、この複合酸化物薄膜の光吸収特性は、酸
化チタン薄膜のそれとほぼ同程度である。In the above general formula, when 0.05 ≦ x ≦ 0.20 and the heat treatment temperature is about 600 ° C. or less, the adhesion between the formed composite oxide thin film and the substrate can be improved, When this is used as a photocatalyst, it gives a practically usable film strength to sewage treatment or the like having a fluidized bed in contact with each other. Further, since the mixing ratio of other metal oxides is low, the light absorption characteristics of this composite oxide thin film are almost the same as those of the titanium oxide thin film.
【００１４】また、殺菌灯(波長254nm)は、蛍光体を使
用しているブラックライトと比較して、エネルギー利用
効率(ランプからの放出エネルギー/ランプへの供給エネ
ルギー)が高く、エネルギーの有効利用を考慮した場
合、殺菌灯を用いた処理システムを構築することが望ま
しい。殺菌灯の放射エネルギーは、4.88eV付近に禁制帯
幅を有しており、酸化力にすぐれた酸化ジルコニウム単
体の禁制帯幅は4.88eV以上であるため、殺菌灯による光
触媒機能の発現は困難である。しかるに、前記一般式に
おいて、0.80≦x<1.00とした場合には、殺菌灯による励
起が可能となる3.2〜4.88eVの禁制帯幅を有する複合酸
化物薄膜を与え、これは光触媒膜として有効である。In addition, the germicidal lamp (wavelength 254 nm) has a higher energy use efficiency (emission energy from the lamp / supply energy to the lamp) than a black light using a fluorescent substance, and has an effective use of energy. In consideration of the above, it is desirable to construct a processing system using a germicidal lamp. The radiant energy of the germicidal lamp has a forbidden band around 4.88 eV, and the forbidden band of zirconium oxide alone, which has excellent oxidizing power, is 4.88 eV or more. is there. However, in the above general formula, when 0.80 ≦ x <1.00, a composite oxide thin film having a forbidden band width of 3.2 to 4.88 eV capable of being excited by a germicidal lamp is provided, which is effective as a photocatalytic film. is there.
【００１５】[0015]
【発明の効果】このようにして調製されたチタン-ジル
コニウム複合酸化物薄膜は、無定形結晶を有するためジ
ルコニア含有率の値を幅広くかつ詳細に設定することが
できる。また、ジルコニア含有率の制御によって、TiO2
吸収端波長(388nm)とZrO2の吸収端波長(248nm)との間に
新たな吸収域を形成させ、殺菌灯の波長(254nm)に対応
した光吸収特性を有する光触媒の調製を可能としてい
る。The titanium-zirconium composite oxide thin film thus prepared has an amorphous crystal, so that the value of the zirconia content can be set widely and in detail. Also, by controlling the zirconia content, TiO 2
A new absorption region is formed between the absorption edge wavelength (388 nm) and the absorption edge wavelength of ZrO 2 (248 nm), making it possible to prepare a photocatalyst having light absorption characteristics corresponding to the germicidal lamp wavelength (254 nm). .
【００１６】[0016]
【実施例】次に、実施例について本発明を説明する。Next, the present invention will be described by way of examples.
【００１７】実施例１ 0.8モル濃度のテトライソプロポキシチタンのエチレン
グリコールモノメチルエーテル(EGME)溶液10mlおよび0.
2モル濃度のテトライソプロポキシジルコニウムのEGME
溶液10mlを混合した後、そこに10重量%塩酸0.42mlをEGM
E10.58mlに溶解させた溶液を撹拌しながら滴下し、Ti-Z
r含有加水分解ゾルを調製した。Example 1 10 ml of a 0.8 molar solution of tetraisopropoxytitanium in ethylene glycol monomethyl ether (EGME) and 0.1 ml
EGME of 2 molar tetraisopropoxy zirconium
After mixing 10 ml of the solution, 0.42 ml of 10% by weight hydrochloric acid was added to the EGM.
E The solution dissolved in 10.58 ml was added dropwise with stirring, and Ti-Z
An r-containing hydrolysis sol was prepared.
【００１８】この加水分解ゾルを用いたディッピング法
により、石英ガラス基板上にゲル化膜を形成させ、昇温
速度5℃/分で500℃迄昇温させ、500℃で10分間加熱処理
して、膜厚30nmの複合酸化物薄膜を得た。図1〜2(x=0.
2)に示されるX線回析パターンおよび光吸収特性から、
この複合酸化物薄膜は無定形結晶構造を有しており、ま
たTiO2(x=0)の吸収スペクトルと比較して短波長側へシ
フトしていることが分り、波長250nmにおいて強い吸収
を示している。A gelling film is formed on a quartz glass substrate by a dipping method using the hydrolyzed sol, the temperature is raised to 500 ° C. at a rate of 5 ° C./min, and heat treatment is performed at 500 ° C. for 10 minutes. Thus, a composite oxide thin film having a thickness of 30 nm was obtained. Figures 1-2 (x = 0.
From the X-ray diffraction pattern and light absorption characteristics shown in 2),
This composite oxide thin film has an amorphous crystal structure, and is found to be shifted to a shorter wavelength side as compared with the absorption spectrum of TiO 2 (x = 0), showing strong absorption at a wavelength of 250 nm. ing.
【００１９】実施例２ 実施例1において、テトライソプロポキシチタンおよび
テトライソプロポキシジルコニウムのEGME溶液濃度が0.
6モルおよび0.4モルにそれぞれ変更された。得られた複
合酸化物薄膜(x=0.4)の図1〜2に示されるX線回析パター
ンおよび光吸収特性から、このものは無定形結晶構造を
有しており、またTiO2の吸収スペクトルと比較して短波
長側へシフトしていることが分り、波長250nmにおいて
強い吸収を示している。Example 2 In Example 1, the concentration of tetraisopropoxytitanium and tetraisopropoxyzirconium in the EGME solution was set at 0.
It was changed to 6 mol and 0.4 mol, respectively. From the X-ray diffraction pattern and light absorption characteristics shown in FIGS. 1 and 2 of the obtained composite oxide thin film (x = 0.4), it has an amorphous crystal structure, and the absorption spectrum of TiO 2 It can be seen that the wavelength is shifted to the shorter wavelength side as compared with that of FIG.
【００２０】実施例３ 実施例1において、テトライソプロポキシチタンおよび
テトライソプロポキシジルコニウムのEGME溶液濃度が0.
5モルおよび0.5モルにそれぞれ変更された。得られた複
合酸化物薄膜(x=0.5)の図1〜2に示されるX線回析パター
ンおよび光吸収特性から、このものは無定形結晶構造を
有しており、またTiO2の吸収スペクトルと比較して短波
長側へシフトしていることが分り、波長250nmにおいて
強い吸収を示している。Example 3 In Example 1, the concentration of tetraisopropoxytitanium and tetraisopropoxyzirconium in the EGME solution was 0.2.
It was changed to 5 mol and 0.5 mol, respectively. From the X-ray diffraction pattern and light absorption characteristics shown in FIGS. 1 and 2 of the obtained composite oxide thin film (x = 0.5), it has an amorphous crystal structure, and the absorption spectrum of TiO 2 It can be seen that the wavelength is shifted to the shorter wavelength side as compared with that of FIG.
【００２１】実施例４ 実施例1において、テトライソプロポキシチタンおよび
テトライソプロポキシジルコニウムのEGME溶液濃度が0.
4モルおよび0.6モルにそれぞれ変更された。得られた複
合酸化物薄膜(x=0.6)の図1〜2に示されるX線回析パター
ンおよび光吸収特性から、このものは無定形結晶構造を
有しており、またTiO2の吸収スペクトルと比較して短波
長側へシフトしていることが分り、波長250nmにおいて
強い吸収を示している。Example 4 In Example 1, the concentration of tetraisopropoxytitanium and tetraisopropoxyzirconium in the EGME solution was adjusted to 0.2.
It was changed to 4 mol and 0.6 mol respectively. From the X-ray diffraction pattern and light absorption characteristics shown in FIGS. 1 and 2 of the obtained composite oxide thin film (x = 0.6), it has an amorphous crystal structure, and the absorption spectrum of TiO 2 It can be seen that the wavelength is shifted to the shorter wavelength side as compared with that of FIG.
【００２２】実施例５ 実施例1において、テトライソプロポキシチタンおよび
テトライソプロポキシジルコニウムのEGME溶液濃度が0.
2モルおよび0.8モルにそれぞれ変更された。得られた複
合酸化物薄膜(x=0.8)の図1〜2に示されるX線回析パター
ンおよび光吸収特性から、このものは無定形結晶構造を
有しており、またTiO2の吸収スペクトルと比較して短波
長側へシフトしていることが分り、波長250nmにおいて
強い吸収を示している。Example 5 In Example 1, the concentration of tetraisopropoxytitanium and tetraisopropoxyzirconium in the EGME solution was 0.2%.
It was changed to 2 mol and 0.8 mol, respectively. From the X-ray diffraction pattern and light absorption characteristics shown in FIGS. 1 and 2 of the obtained composite oxide thin film (x = 0.8), it has an amorphous crystal structure, and the absorption spectrum of TiO 2 It can be seen that the wavelength is shifted to the shorter wavelength side as compared with that of FIG.
【００２３】比較例１ 1.0モル濃度のテトライソプロポキシチタンのEGME溶液2
0mlに、10重量%塩酸0.42mlをEGME10.58mlに溶解させた
溶液を撹拌しながら滴下し、Ti含有加水分解ゾルを調製
した。この加水分解ゾルを用いたディッピング法によ
り、石英ガラス基板上にゲル化膜を形成させ、昇温速度
5℃/分で500℃迄昇温させ、500℃で10分間加熱処理し
て、膜厚30nmの酸化チタン薄膜を得た。Comparative Example 1 EGME solution 2 of 1.0 molar concentration of tetraisopropoxytitanium
A solution in which 0.42 ml of 10% by weight hydrochloric acid was dissolved in 10.58 ml of EGME was added dropwise to 0 ml with stirring to prepare a Ti-containing hydrolysis sol. A gelling film is formed on a quartz glass substrate by the dipping method using this hydrolysis sol,
The temperature was raised to 500 ° C. at a rate of 5 ° C./min, and heat treatment was performed at 500 ° C. for 10 minutes to obtain a titanium oxide thin film having a thickness of 30 nm.
【００２４】図1〜2(x=0)に示されるX線回析パターンお
よび光吸収特性から、この酸化チタン薄膜は正方晶系ア
ナターゼ型構造(図1に○で示される)をしており、波長2
75nmにおいて強い吸収を示した。From the X-ray diffraction patterns and light absorption characteristics shown in FIGS. 1 and 2 (x = 0), this titanium oxide thin film has a tetragonal anatase type structure (indicated by a circle in FIG. 1). , Wavelength 2
It showed strong absorption at 75 nm.
【００２５】比較例２ 比較例1において、テトライソプロポキシチタンのEGME
溶液の代りに、同濃度、同量のテトライソプロポキシジ
ルコニウムのEGME溶液が用いられた。図1〜2(x=1.0)に
示されるX線回析パターンおよび光吸収特性から、この
酸化ジルコニウム薄膜は単斜晶系ホタル石構造(図1に●
で示される)を有しており、波長200nm以下に強い吸収域
があると推定される。Comparative Example 2 In Comparative Example 1, the EGME of tetraisopropoxy titanium was used.
Instead of the solution, an EGME solution of the same concentration and the same amount of tetraisopropoxy zirconium was used. From the X-ray diffraction patterns and light absorption characteristics shown in FIGS. 1-2 (x = 1.0), this zirconium oxide thin film has a monoclinic fluorite structure (Fig.
It is estimated that there is a strong absorption region at a wavelength of 200 nm or less.
【００２６】実施例６ 実施例1において、テトライソプロポキシチタンおよび
テトライソプロポキシジルコニウムのEGME溶液濃度がそ
れぞれ0.95モルおよび0.05モルにそれぞれ変更された。
この複合酸化物薄膜の基板に対する付着性をひっかき法
によって測定すると、目視による傷の形成が確認されず
良好であった。また、光吸収可能な波長λは360nm以下
であった。Example 6 In Example 1, the EGME solution concentrations of tetraisopropoxytitanium and tetraisopropoxyzirconium were changed to 0.95 mol and 0.05 mol, respectively.
When the adhesion of the composite oxide thin film to the substrate was measured by a scratching method, the formation of scratches by visual inspection was good, and it was good. The wavelength λ at which light can be absorbed was 360 nm or less.
【００２７】更に、水溶液中のイソプロパノールの光酸
化分解が行われることから、この複合酸化物薄膜が光触
媒活性を有することが確認された。即ち、濃度1000ppm
のイソプロパノール水溶液中に、30×10mmの大きさの複
合酸化薄膜を形成させた基板を浸せきし、これに出力10
Ｗのブラックライトブルーによる光を照射し、イソプロ
パノールの光酸化分解を実施すると、光照射によるイソ
プロパノール濃度の減少がガスクロマトグラフィーによ
って確認された。Further, photooxidative decomposition of isopropanol in the aqueous solution was carried out, confirming that the composite oxide thin film had photocatalytic activity. That is, concentration 1000ppm
The substrate on which the composite oxide thin film with the size of 30 × 10 mm is formed is immersed in the isopropanol aqueous solution of
When light irradiation was performed with black light blue of W to perform photooxidative decomposition of isopropanol, a decrease in the isopropanol concentration due to light irradiation was confirmed by gas chromatography.
【００２８】なお、実施例1で得られた複合酸化物薄膜
についても、これと全く同様の上記3つの特性が確認さ
れた。また、比較例1で得られた酸化チタン薄膜につい
ては、光吸収可能な波長λは360nm以下であったが、基
板に対する付着性は、目視による傷の形成が確認され、
不良であった。It should be noted that the composite oxide thin film obtained in Example 1 was confirmed to have the same three characteristics as described above. In addition, for the titanium oxide thin film obtained in Comparative Example 1, the wavelength λ at which light can be absorbed was 360 nm or less, but the adhesion to the substrate was confirmed by the formation of scratches visually.
It was bad.
【００２９】実施例７ 実施例1において、テトライソプロポキシチタンおよび
テトライソプロポキシジルコニウムのEGME溶液濃度が0.
10モルおよび0.90モルにそれぞれ変更された。得られた
膜厚80nmの複合酸化物薄膜の光吸収スペクトルを測定す
ると、図3のグラフの(a)に示されるような結果が得ら
れ、ZrO2単体薄膜の場合(c)と比較して、長波長側への
シフトが認められた。また、4.88eVの殺菌灯のエネルギ
ーに対しても吸収を示すことから、禁制帯幅は4.88eV以
下であった。Example 7 In Example 1, the concentration of tetraisopropoxytitanium and tetraisopropoxyzirconium in the EGME solution was set at 0.
It was changed to 10 mol and 0.90 mol, respectively. When the light absorption spectrum of a composite oxide thin film of the resulting film thickness 80nm to measure, results as shown in (a) in the graph of FIG. 3 can be obtained, as compared with the case of ZrO 2 alone film (c) , A shift toward longer wavelengths was observed. In addition, the energy absorption of the germicidal lamp of 4.88 eV shows absorption, so the forbidden band width was 4.88 eV or less.
【００３０】なお、実施例5で得られた複合酸化物薄膜
の光吸収スペクトルは、図3の(d)に示される。曲線の立
上りは、(a)、(b)の場合と比べて低エネルギー側で観察
され、酸化能力は(a)、(b)の場合と比較して低いと考え
られる。The light absorption spectrum of the composite oxide thin film obtained in Example 5 is shown in FIG. The rise of the curve is observed on the lower energy side as compared with the cases (a) and (b), and it is considered that the oxidizing ability is lower than the cases (a) and (b).
【００３１】実施例８ 実施例1において、テトライソプロポキシチタンおよび
テトライソプロポキシジルコニウムのEGME溶液濃度が0.
05モルおよび0.95モルにそれぞれ変更された。得られた
膜厚80nmの複合酸化物薄膜の光吸収スペクトルを測定す
ると、図3のグラフの(b)に示されるような結果が得ら
れ、ZrO2単体薄膜の場合(c)と比較して、長波長側への
シフトが認められた。また、4.88eVの殺菌灯のエネルギ
ーに対しても吸収を示すことから、禁制帯幅は4.88eV以
下であった。Example 8 In Example 1, the concentration of tetraisopropoxytitanium and tetraisopropoxyzirconium in the EGME solution was set at 0.
It was changed to 05 mol and 0.95 mol, respectively. When the light absorption spectrum of the obtained composite oxide thin film having a thickness of 80 nm was measured, the result as shown in the graph (b) of FIG. 3 was obtained, which was compared with the case of the ZrO 2 simple thin film (c). , A shift toward longer wavelengths was observed. In addition, the energy absorption of the germicidal lamp of 4.88 eV shows absorption, so the forbidden band width was 4.88 eV or less.
【図１】各ジルコニウム含有率(x)における酸化物薄膜
の結晶構造を示すグラフである。FIG. 1 is a graph showing the crystal structure of an oxide thin film at each zirconium content (x).
【図２】各ジルコニウム含有率(x)における酸化物薄膜
の光吸収特性を示すグラフである。FIG. 2 is a graph showing light absorption characteristics of an oxide thin film at each zirconium content (x).
【図３】実施例7〜8で得られた複合酸化物薄膜の光吸収
スペクトルを示すグラフである。FIG. 3 is a graph showing light absorption spectra of the composite oxide thin films obtained in Examples 7 and 8.
Claims (7)
酸化チタン以外の金属酸化物からなる複合酸化物薄膜。1. A composite oxide thin film comprising a metal oxide other than titanium oxide and titanium oxide having a forbidden band width of 3.2 eV or more.
金属酸化物であり、0.05≦x<1.00であり、yは金属Mに対
応する酸化物酸素数である)で表わされる請求項1記載の
複合酸化物薄膜。2. The general formula (1-x) TiO 2 .xMO y (where MO y is a metal oxide other than titanium oxide having a band gap other than 3.2 eV, 0.05 ≦ x <1.00, y Is the oxide oxygen number corresponding to the metal M).
有する請求項２記載の複合酸化物薄膜。3. The composite oxide thin film according to claim 2, wherein 0.1 ≦ x ≦ 0.9 and has an amorphous crystal structure.
長λが360nm以下である請求項2記載の複合酸化物薄膜。4. The composite oxide thin film according to claim 2, wherein 0.05 ≦ x ≦ 0.20, and the wavelength λ capable of light absorption is 360 nm or less.
媒機能を発揮する請求項2記載の複合酸化物薄膜。5. The composite oxide thin film according to claim 2, wherein 0.80 ≦ x <1.00, and exhibits a photocatalytic function by a germicidal lamp.
3、4または5記載の複合酸化物薄膜。6. The method according to claim 1, which is used as a photocatalyst.
6. The composite oxide thin film according to 3, 4, or 5.
以上の禁制帯幅を有するチタン以外の金属の有機金属化
合物の混合物有機溶媒溶液に無機酸または有機酸を添加
してチタンおよび他の金属を含有する加水分解ゾルを形
成させ、このゾルを基板上に塗布してゲル膜を形成させ
た後、約300〜1200℃の温度で加熱処理することを特徴
とする請求項1または2記載の複合酸化物薄膜の製造法。7. The organic titanium compound and the oxide are 3.2 eV.
A mixture of an organometallic compound of a metal other than titanium having the above forbidden band width, an inorganic acid or an organic acid is added to an organic solvent solution to form a hydrolysis sol containing titanium and other metals, and the sol is placed on a substrate. 3. The method for producing a composite oxide thin film according to claim 1, wherein a heat treatment is performed at a temperature of about 300 to 1200 [deg.] C. after forming a gel film by applying the composition to a thin film.
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|---|---|---|---|
| JP20083897 | 1997-07-10 | ||
| JP9-200838 | 1997-07-10 | ||
| JP16939898A JP3799822B2 (en) | 1997-07-10 | 1998-06-17 | Manufacturing method of complex oxide thin film |
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ID=26492746
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001162176A (en) * | 1999-12-06 | 2001-06-19 | Nitto Denko Corp | Photocatalytic body |
| JP2003093890A (en) * | 2001-09-25 | 2003-04-02 | Mitsubishi Heavy Ind Ltd | Method for preparing photocatalyst |
| US7148387B2 (en) | 2003-05-28 | 2006-12-12 | Mitsui Chemicals, Inc. | Process for producing hydroxyl group-containing compound |
| JP2009213954A (en) * | 2008-03-07 | 2009-09-24 | Univ Of Tokyo | Thin film, its manufacturing method and glass |
| WO2013100021A1 (en) * | 2011-12-29 | 2013-07-04 | Toto株式会社 | Composite material and coating composition |
| WO2018088966A1 (en) | 2016-11-11 | 2018-05-17 | National University Of Singapore | Thin film deposited amorphous inorganic metal oxide as a selective substrate for mammalian cell culture and as an implant coating |
-
1998
- 1998-06-17 JP JP16939898A patent/JP3799822B2/en not_active Expired - Fee Related
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001162176A (en) * | 1999-12-06 | 2001-06-19 | Nitto Denko Corp | Photocatalytic body |
| JP2003093890A (en) * | 2001-09-25 | 2003-04-02 | Mitsubishi Heavy Ind Ltd | Method for preparing photocatalyst |
| US7148387B2 (en) | 2003-05-28 | 2006-12-12 | Mitsui Chemicals, Inc. | Process for producing hydroxyl group-containing compound |
| JP2009213954A (en) * | 2008-03-07 | 2009-09-24 | Univ Of Tokyo | Thin film, its manufacturing method and glass |
| WO2013100021A1 (en) * | 2011-12-29 | 2013-07-04 | Toto株式会社 | Composite material and coating composition |
| WO2018088966A1 (en) | 2016-11-11 | 2018-05-17 | National University Of Singapore | Thin film deposited amorphous inorganic metal oxide as a selective substrate for mammalian cell culture and as an implant coating |
| CN110234784A (en) * | 2016-11-11 | 2019-09-13 | 新加坡国立大学 | The film of deposited amorphous state inorganic, metal oxide is as the selective substrate for mammaliancellculture and as implantation material coating |
| US11795430B2 (en) | 2016-11-11 | 2023-10-24 | National University Of Singapore | Thin film deposited inorganic metal oxide as a selective substrate for mammalian cell culture and as an implant coating |
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| Publication number | Publication date |
|---|---|
| JP3799822B2 (en) | 2006-07-19 |
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