JPH0478340B2 - - Google Patents
Info
- Publication number
- JPH0478340B2 JPH0478340B2 JP61021295A JP2129586A JPH0478340B2 JP H0478340 B2 JPH0478340 B2 JP H0478340B2 JP 61021295 A JP61021295 A JP 61021295A JP 2129586 A JP2129586 A JP 2129586A JP H0478340 B2 JPH0478340 B2 JP H0478340B2
- Authority
- JP
- Japan
- Prior art keywords
- film
- ultrafine
- particles
- thin film
- ultrafine particle
- 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.)
- Expired
Links
- 239000011882 ultra-fine particle Substances 0.000 claims description 73
- 239000010408 film Substances 0.000 claims description 58
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims description 39
- 239000002243 precursor Substances 0.000 claims description 32
- 239000010409 thin film Substances 0.000 claims description 26
- 239000002245 particle Substances 0.000 claims description 22
- 238000004519 manufacturing process Methods 0.000 claims description 19
- 239000000758 substrate Substances 0.000 claims description 16
- 229910052697 platinum Inorganic materials 0.000 claims description 15
- 239000003054 catalyst Substances 0.000 claims description 7
- 238000006243 chemical reaction Methods 0.000 claims description 7
- 230000003197 catalytic effect Effects 0.000 claims description 4
- 239000000446 fuel Substances 0.000 claims description 2
- 238000000034 method Methods 0.000 description 41
- 150000001875 compounds Chemical class 0.000 description 32
- 239000012528 membrane Substances 0.000 description 14
- 239000000126 substance Substances 0.000 description 14
- 239000000463 material Substances 0.000 description 9
- 229910021397 glassy carbon Inorganic materials 0.000 description 8
- 238000005755 formation reaction Methods 0.000 description 7
- 125000002091 cationic group Chemical group 0.000 description 6
- 229910052751 metal Inorganic materials 0.000 description 6
- 238000006722 reduction reaction Methods 0.000 description 6
- 239000000243 solution Substances 0.000 description 6
- 125000000129 anionic group Chemical group 0.000 description 5
- 238000010348 incorporation Methods 0.000 description 5
- 239000002184 metal Substances 0.000 description 5
- 238000007740 vapor deposition Methods 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- 238000005516 engineering process Methods 0.000 description 4
- 239000007789 gas Substances 0.000 description 4
- 239000012071 phase Substances 0.000 description 4
- 230000009467 reduction Effects 0.000 description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 3
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 3
- 125000000217 alkyl group Chemical group 0.000 description 3
- 239000007864 aqueous solution Substances 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 3
- 229910052799 carbon Inorganic materials 0.000 description 3
- 239000003638 chemical reducing agent Substances 0.000 description 3
- 239000001257 hydrogen Substances 0.000 description 3
- 229910052739 hydrogen Inorganic materials 0.000 description 3
- 230000002209 hydrophobic effect Effects 0.000 description 3
- 150000002500 ions Chemical class 0.000 description 3
- 239000007791 liquid phase Substances 0.000 description 3
- 238000006552 photochemical reaction Methods 0.000 description 3
- 150000003839 salts Chemical class 0.000 description 3
- 239000011734 sodium Substances 0.000 description 3
- OAKJQQAXSVQMHS-UHFFFAOYSA-N Hydrazine Chemical compound NN OAKJQQAXSVQMHS-UHFFFAOYSA-N 0.000 description 2
- 229940081735 acetylcellulose Drugs 0.000 description 2
- 150000001450 anions Chemical class 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- 229920002301 cellulose acetate Polymers 0.000 description 2
- 238000007385 chemical modification Methods 0.000 description 2
- 239000000460 chlorine Substances 0.000 description 2
- 239000010419 fine particle Substances 0.000 description 2
- 239000003446 ligand Substances 0.000 description 2
- 150000004767 nitrides Chemical class 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 238000000053 physical method Methods 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- 238000001556 precipitation Methods 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 238000006479 redox reaction Methods 0.000 description 2
- 238000000935 solvent evaporation Methods 0.000 description 2
- 238000005979 thermal decomposition reaction Methods 0.000 description 2
- 101710134784 Agnoprotein Proteins 0.000 description 1
- ROFVEXUMMXZLPA-UHFFFAOYSA-N Bipyridyl Chemical group N1=CC=CC=C1C1=CC=CC=N1 ROFVEXUMMXZLPA-UHFFFAOYSA-N 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- 101150003085 Pdcl gene Proteins 0.000 description 1
- XBDQKXXYIPTUBI-UHFFFAOYSA-M Propionate Chemical compound CCC([O-])=O XBDQKXXYIPTUBI-UHFFFAOYSA-M 0.000 description 1
- 239000006087 Silane Coupling Agent Substances 0.000 description 1
- SMEGJBVQLJJKKX-HOTMZDKISA-N [(2R,3S,4S,5R,6R)-5-acetyloxy-3,4,6-trihydroxyoxan-2-yl]methyl acetate Chemical compound CC(=O)OC[C@@H]1[C@H]([C@@H]([C@H]([C@@H](O1)O)OC(=O)C)O)O SMEGJBVQLJJKKX-HOTMZDKISA-N 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- KXKVLQRXCPHEJC-UHFFFAOYSA-N acetic acid trimethyl ester Natural products COC(C)=O KXKVLQRXCPHEJC-UHFFFAOYSA-N 0.000 description 1
- 238000005054 agglomeration Methods 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 229910010293 ceramic material Inorganic materials 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- REZZEXDLIUJMMS-UHFFFAOYSA-M dimethyldioctadecylammonium chloride Chemical compound [Cl-].CCCCCCCCCCCCCCCCCC[N+](C)(C)CCCCCCCCCCCCCCCCCC REZZEXDLIUJMMS-UHFFFAOYSA-M 0.000 description 1
- 239000012153 distilled water Substances 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 238000003487 electrochemical reaction Methods 0.000 description 1
- 239000012776 electronic material Substances 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 125000003916 ethylene diamine group Chemical group 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 125000001165 hydrophobic group Chemical group 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 229910010272 inorganic material Inorganic materials 0.000 description 1
- 239000011147 inorganic material Substances 0.000 description 1
- 239000012212 insulator Substances 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 229910052753 mercury Inorganic materials 0.000 description 1
- 150000001247 metal acetylides Chemical class 0.000 description 1
- 239000011817 metal compound particle Substances 0.000 description 1
- 239000002923 metal particle Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- -1 n-octadecyl Chemical group 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 239000012299 nitrogen atmosphere Substances 0.000 description 1
- 229920000620 organic polymer Polymers 0.000 description 1
- 239000007800 oxidant agent Substances 0.000 description 1
- 239000002861 polymer material Substances 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 238000000197 pyrolysis Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 230000001568 sexual effect Effects 0.000 description 1
- 229910052709 silver Inorganic materials 0.000 description 1
- 239000012279 sodium borohydride Substances 0.000 description 1
- 229910000033 sodium borohydride Inorganic materials 0.000 description 1
- MRQYKJNZWPCFNB-UHFFFAOYSA-M sodium;icosanoate Chemical compound [Na+].CCCCCCCCCCCCCCCCCCCC([O-])=O MRQYKJNZWPCFNB-UHFFFAOYSA-M 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D1/00—Processes for applying liquids or other fluent materials
- B05D1/18—Processes for applying liquids or other fluent materials performed by dipping
- B05D1/20—Processes for applying liquids or other fluent materials performed by dipping substances to be applied floating on a fluid
- B05D1/202—Langmuir Blodgett films (LB films)
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y40/00—Manufacture or treatment of nanostructures
Description
（産業上の利用分野）
本発明は、LB（Langmuir−Blodgett，ラング
ミユアーブロジエツト）膜あるいはそれに類似し
た超薄膜内の超微粒子前駆体から、均一かつ凝集
のない超微粒子を製造する技術に関するものであ
る。
（従来技術とその限界）
粒子径ｄが10分の１ミクロン以下（ｄ100n
ｍ）の金属や金属化合物粒子は超微粒子と呼ば
れ、同じ物質からなる通常の大きさの材料とは物
理的、化学的に異なつた性能、例えば低融点、高
磁気特性、高触媒特性などの特異性を示し、今日
新材料の一つとして注目されている。その製法は
大別すると物理的方法と化学的方法に分けられ、
後者の化学的方法はさらに気相法と液相法とに分
類される。
前記液相法による超微粒子の生成法において
は、組成の制御が容易であるため多成分系化合物
の粒子の形成や微量成分の添加が気相法に比べて
容易であるが、気相法に比べ、粒子径の制御や
粒径分布を狭くすることがより困難であり、また
生成粒子が凝集しやすいなどの欠点を持つてい
る。また、前記物理的方法においては不純物の混
入や粒度構成、特に超微細化に難点がある。
（発明が解決しようとする問題点）
本発明は、前記した従来の超微粒子製造技術の
問題点を克服しようとするもので、
◎粒子径の制御が容易であり、
◎生成超微粒子が凝集せず、
◎しかも、超微粒子を担体上に担持することを目
的とした場合、担持量を精密に制御することが
できる、
超微粒子の新しい製造法を提供しようとするもの
である。
（問題点を解決するための具体的な手段）
本発明者は、前記した従来の問題点を解決すべ
く鋭意検討を加えた結果、
Γ親水性基と疎水性基を一分子内に有する両親媒
性化合物をLB膜装置により基板上に積層した
超薄膜（例えば膜厚、数100Åのもの）内にお
いて、
Γあるいは、両親媒性化合物の希薄溶液から溶媒
蒸発により基板または下地粉体表面にLB膜様
の超薄膜として生じた被覆薄膜内において、
Γさらには、その他の超薄膜技術、例えば蒸着
法、化学修飾法（固体表面にシランカツプリン
グ剤を用いて、化学結合により単分子膜を形成
させる方法）などにより形成した超薄膜内にお
いて、
前記薄膜の形成と同時に膜内に一定量取り込んだ
超微粒子前駆体を、該薄膜と接している溶液また
は下地基板などと反応させて超微粒子に転化させ
ることにより粒径が均一で、凝集のない、かつ、
単位下地面積当りの粒子数（担持量）を制御する
ことができる超微粒子の製造法を見い出し、本発
明に至つた。
この発明を概説すれば、その第１の発明はLB
膜あるいはLB膜様薄膜内で超微粒子前駆体を超
微粒子に転化して調製した超微粒子に関する発明
であり、また第２の発明は前記超微粒子の製造方
法に関する発明であり、さらに第３の発明は本発
明になる超微粒子は多くの用途において原材料あ
るいは中間材として有用であるが、特に触媒に関
する発明であつて、前記第１の発明のLB膜ある
いはLB膜様薄膜内で超微粒子前駆体を超微粒子
に転化して調製した超微粒子からなることを特徴
とする。
以下本発明の具体的な構成について詳しく説明
する。
本発明になる超微粒子製造法の中核的な技術思
想は、前記した如く、基板または下地の上に被覆
形成した、均質で、一定膜厚の、かつ超微粒子前
駆体を含有する超薄膜（LB膜、またはLB膜様の
薄膜）内を超微粒子の形成反応の場に利用すると
いう点であり、この点により（）超微粒子形成
反応が膜面全体にわたつて一定の速度で進行する
ため、生成超微粒子の粒子径が均一化すること、
（）また超微粒子形成反応が膜内で進行するた
め生成した超微粒子は膜内に固定されること、即
ち結果的に膜によつて保護されることから凝集し
ないこと、（）膜厚を制御することにより反応
にあずかる超微粒子前駆体をなす化合物のうち、
特定成分の濃度を単位下地面積当り任意に保つこ
とが可能となるので担持量を精密に制御すること
ができること、という従前にない優れた超微粒子
の製造技術が提供されることになる。
従つて、上述したことから明らかの如くLB膜
あるいはLB膜様の薄膜形成時に薄膜内に同時に
取り込んだ超微粒子前駆体を超微粒子に転化させ
る方法は二次的なものであつて、いずれの化学反
応や処理法をも利用することができる。
例えば還元法、酸化法、沈殿法、光化学反応、
熱分解法など多くの方法が採用できる。また、こ
れに対応して膜内以外の反応種、反応源も各種の
ものがあり、膜に接する溶液中の化合物、膜に接
する気相の化合物、膜の下地の材料、膜の下地を
電極として用いて電気化学的反応によつて超微粒
子形成反応を進める場合の電子、膜中の前駆体化
合物間の反応を光化学反応によつて進行させる場
合の光量子、熱分解反応における温度条件および
環境条件（例えば金属窒化物の微粒子とする場
合、窒素雰囲気下で熱分解する）などには何らの
制約もない。
次に、本発明になる超微粒子製造法において、
薄膜（LB膜あるいはLB膜様薄膜）形成時に、該
薄膜内に取り込ませる超微粒子前駆体について説
明する。
前記超微粒子前駆体は、採用する製膜技術に関
係するので、それとの関連で説明する。本発明に
おいてLB膜あるいはLB膜様薄膜とは次のことを
意味する。
LB膜とは両親媒性化合物、即ち一分子内に親
水性基と親油性基を有し、かつ水面上に単分子膜
として展開できる水不溶性の化合物を、LB膜製
造装置を用いて下地基板上に単分子膜として移し
取つたもの、あるいは前記単分子膜層を何層にも
積層して移し取つたものである。膜厚は積層回数
にもよるが例えば数100Åのものも含まれる超薄
膜状のものである。LB膜様薄膜とは、蒸着手段
などを用いて調製したLB膜様の超薄膜のことを
いう。そして、本発明においては超微粒子前駆体
をLB膜あるいはLB膜様薄膜の製膜時に膜内に取
り込ませるもので、その取り込みの態様として次
のものが例示される。
陽イオン基又は陰イオン基を有する両親媒性
化合物と対イオンとなるもの、即ち超微粒子前
駆体として陰イオンとなるもの、即ち超微粒子
前駆体として陰イオン型又は陽イオン型の金属
塩を用いて取り込ませるもの。
この場合、両親媒性化合物に超微粒子前駆体
がイオン結合することにより、両親媒性化合物
のLB製膜時に超微粒子前駆体を膜内に取り込
むことができる。
両親媒性化合物と超微粒子前駆体を配位結合
させて取り込ませるもの。
両親媒性化合物、それ自身が超微粒子前駆体
であるものを用いて取り込ませるもの。
次に、前記の取り込ませ方法、即ち超微粒子
前駆体を両親媒性化合物とイオン結合させてLB
膜内に取り込ませる方法について説明する。
() 両親媒性化合物として、
(Industrial Application Field) The present invention relates to a technique for producing uniform, non-agglomerated ultrafine particles from ultrafine particle precursors in an LB (Langmuir-Blodgett) film or a similar ultrathin film. It is something. (Conventional technology and its limitations) Particle diameter d is 1/10 micron or less (d100n
The metal or metal compound particles (m) are called ultrafine particles, and they have physical and chemical properties that are different from normal-sized materials made of the same substance, such as low melting point, high magnetic properties, and high catalytic properties. Due to its unique properties, it is attracting attention as a new material today. The manufacturing methods can be broadly divided into physical methods and chemical methods.
The latter chemical methods are further classified into gas phase methods and liquid phase methods. In the method for producing ultrafine particles using the liquid phase method, it is easier to control the composition, so it is easier to form particles of multicomponent compounds and add trace components than in the gas phase method. In comparison, it is more difficult to control the particle size and narrow the particle size distribution, and the produced particles tend to aggregate. In addition, the above-mentioned physical methods have drawbacks such as the incorporation of impurities and the particle size structure, particularly in ultra-fine refinement. (Problems to be Solved by the Invention) The present invention attempts to overcome the problems of the conventional ultrafine particle manufacturing technology described above. ◎Moreover, when the purpose is to support ultrafine particles on a carrier, the present invention aims to provide a new method for producing ultrafine particles that allows precise control of the amount of ultrafine particles supported. (Specific Means for Solving the Problems) As a result of intensive studies to solve the above-mentioned conventional problems, the inventors of the present invention discovered that a parent compound having a Γ hydrophilic group and a hydrophobic group in one molecule In an ultra-thin film (for example, a film thickness of several hundred Å) in which a medium compound is laminated on a substrate using an LB film device, LB is applied to the surface of the substrate or base powder by solvent evaporation from a dilute solution of Γ or an amphiphilic compound. In addition, other ultra-thin film techniques such as vapor deposition and chemical modification methods (using a silane coupling agent on the solid surface to form a monomolecular film through chemical bonding) In an ultra-thin film formed by a method such as the above-described method, a certain amount of ultra-fine particle precursor is incorporated into the film at the same time as the thin film is formed, and is converted into ultra-fine particles by reacting with a solution or a base substrate in contact with the thin film. By doing so, the particle size is uniform, there is no agglomeration, and
We have discovered a method for producing ultrafine particles that allows the number of particles (supported amount) per unit base area to be controlled, leading to the present invention. To summarize this invention, the first invention is LB
This invention relates to ultrafine particles prepared by converting an ultrafine particle precursor into ultrafine particles within a film or LB film-like thin film, and a second invention relates to a method for producing the ultrafine particles, and a third invention relates to a method for producing the ultrafine particles. Although the ultrafine particles of the present invention are useful as raw materials or intermediate materials in many applications, this invention is particularly related to catalysts, and is an invention in which ultrafine particle precursors are used in the LB film or LB film-like thin film of the first invention. It is characterized by consisting of ultrafine particles prepared by converting them into ultrafine particles. The specific configuration of the present invention will be explained in detail below. As mentioned above, the core technical idea of the method for producing ultrafine particles of the present invention is that the ultrathin film (LB) is formed on a substrate or base, is homogeneous, has a constant thickness, and contains an ultrafine particle precursor. The point is that the inside of the membrane (or a thin film like LB film) is used as a site for the ultrafine particle formation reaction, and because () the ultrafine particle formation reaction proceeds at a constant speed over the entire membrane surface, The particle diameter of the generated ultrafine particles is made uniform;
() In addition, since the ultrafine particle formation reaction proceeds within the membrane, the generated ultrafine particles are fixed within the membrane, that is, they are protected by the membrane and do not aggregate, and () the film thickness is controlled. Among the compounds forming ultrafine particle precursors that participate in the reaction by
Since it becomes possible to maintain the concentration of a specific component at any value per unit base area, it is possible to precisely control the amount supported, which provides an unprecedented and excellent ultrafine particle manufacturing technology. Therefore, as is clear from the above, the method of converting the ultrafine particle precursors simultaneously incorporated into the thin film into ultrafine particles during the formation of the LB film or LB-like thin film is a secondary method, and cannot be used with any chemical method. Reactions and treatment methods can also be used. For example, reduction method, oxidation method, precipitation method, photochemical reaction,
Many methods can be employed, including pyrolysis. Correspondingly, there are various reactive species and reaction sources outside the membrane, such as compounds in the solution in contact with the membrane, compounds in the gas phase in contact with the membrane, materials for the base of the membrane, and electrodes for the base of the membrane. electrons when the ultrafine particle forming reaction is advanced by an electrochemical reaction, photons when the reaction between precursor compounds in the film is advanced by a photochemical reaction, temperature conditions and environmental conditions in a thermal decomposition reaction. (For example, when forming fine particles of metal nitride, it is thermally decomposed in a nitrogen atmosphere.) There are no restrictions at all. Next, in the method for producing ultrafine particles according to the present invention,
The ultrafine particle precursor incorporated into the thin film (LB film or LB film-like thin film) when forming the thin film will be explained. The ultrafine particle precursor is related to the film forming technology employed, so it will be explained in relation to that. In the present invention, LB film or LB film-like thin film means the following. LB film is an amphiphilic compound, that is, a water-insoluble compound that has a hydrophilic group and a lipophilic group in one molecule and can be spread as a monomolecular film on the water surface, and is made by using an LB film manufacturing equipment to coat a base substrate. A monomolecular film is transferred onto the substrate, or a plurality of monomolecular film layers are stacked and transferred. Although the thickness of the film depends on the number of times it is laminated, it is an ultra-thin film that can be several hundred angstroms thick, for example. The LB film-like thin film refers to an LB film-like ultra-thin film prepared using a vapor deposition method or the like. In the present invention, the ultrafine particle precursor is incorporated into the LB film or LB film-like thin film during film formation, and the following are examples of modes of incorporation. An amphipathic compound having a cationic group or an anionic group and a counter ion, that is, a substance that becomes an anion as an ultrafine particle precursor, that is, an anionic or cationic metal salt is used as an ultrafine particle precursor. something to be taken in. In this case, by ionic bonding of the ultrafine particle precursor to the amphipathic compound, the ultrafine particle precursor can be incorporated into the film during LB film formation of the amphipathic compound. An amphipathic compound and an ultrafine particle precursor are incorporated by coordinate bonding. Amphiphilic compounds, which are themselves ultrafine particle precursors, are used to incorporate them. Next, use the above-mentioned incorporation method, that is, ionically bond the ultrafine particle precursor with an amphipathic compound to LB.
The method of incorporating it into the membrane will be explained. () As an amphipathic compound,
【式】【formula】
【式】【formula】
【式】
などの陽イオン基を有し、かつ１または２本の
長鎖アルキル基を有する化合物、例えば
で示されるものを用いる場合。より具体的に
は、上記化学構造式(1)においてｎ＝18、ｍ＝２
のものはＮ−メチル−N′−〔３−ピロピルアミ
ド−N′，N′−ジ（ｎ−オクタデシル）〕−４，
４−ビピリジニウム−ジブロマイドであり、上
記化学構造式(2)においてｎ＝18のものはジオク
タデシル−ジメチル アンモニウム クロライ
ドである。
前記陽イオン基含有の両親媒性化合物に対し
て、対イオン形成化合物、即ち陰イオン型金属
塩を超微粒子前駆体として用いる。
具体的にはH2PtCl6，HAuCl4，H2RuCl5，
H3RhCl6，H2PdCl4，H2IrCl6などが用いられ
る。
H2PtCl6の水溶液上において、前記陽イオン
基含有の両親媒性化合物を用いて下地基板上に
LB膜を形成させるとき、２価の陰イオンであ
るPtCl-- 6が両親媒性化合物とイオン結合し、
PtCl-- 6を対イオンとしたLB膜が下地基板上に
移し取られる。別言すれば、対イオンの形で超
微粒子前駆体としてのPt（白金）成分がLB膜内
に取り込まれることになる。
() 両親媒性化合物として、
−COO-，−SO3 -，SO4 -，
Compounds having a cationic group such as [Formula] and one or two long-chain alkyl groups, such as When using the one shown in . More specifically, in the chemical structural formula (1) above, n=18, m=2
N-methyl-N'-[3-propylamido-N',N'-di(n-octadecyl)]-4,
It is 4-bipyridinium dibromide, and in the chemical structural formula (2) above, n=18 is dioctadecyl-dimethyl ammonium chloride. For the cationic group-containing amphipathic compound, a counterion-forming compound, that is, an anionic metal salt, is used as an ultrafine particle precursor. Specifically, H 2 PtCl 6 , HAuCl 4 , H 2 RuCl 5 ,
H 3 RhCl 6 , H 2 PdCl 4 , H 2 IrCl 6 and the like are used. On an aqueous solution of H 2 PtCl 6 , the above cationic group-containing amphiphilic compound is used to coat the base substrate.
When forming an LB film, PtCl -- 6 , a divalent anion, ionically bonds with an amphipathic compound,
An LB film with PtCl -- 6 as a counterion is transferred onto the underlying substrate. In other words, the Pt (platinum) component as an ultrafine particle precursor is incorporated into the LB film in the form of counter ions. () As an amphipathic compound, −COO − , −SO 3 − , SO 4 − ,
【式】【formula】
【式】
などの陰イオン基を有し、かつ一または二本の
長鎖アルキル基を有する化合物、例えば
CoH2o+1−COO-Na+ (6)
CoH2o+1−SO4 -Na+ (7)
で示されるものを用いる場合。より具体的に
は、上記化学構造式(6)においてｎ＝19のものは
アラキジン酸ナトリウムである。
前記陰イオン基含有の両親媒性化合物に対し
て、対イオン形成化合物、即ち陽イオン型金属
塩を超微粒子前駆体として用いる。具体的には
Ni（NO3）2，AgNO3，Hg（NO3）2などが用いら
れ、Na+の代りにNi2+，Ag+，Hg2+を対イオ
ンとしたLB膜がつくられる。これらの対イオ
ンを還元するとNi，Ag，Hgの超微粒子が得
られる。
また、前記取り込ませ方法としては、下記
化学構造式（11），（12）に示されるように、配
位結合で超微粒子前駆体としてのPt，Cr成分
を親水性基に取り込んでいる両親媒性化合物を
用いたり、
あるいは下記化学構造式（13），（14）に示され
るようなエチレンジアミン部位、ビピリジン部
位などを親水性基とし、かつ二本の長鎖アルキ
ル基Ｒを有する配位子、即ち配位能を有する両
親媒性化合物をCu2+，Ni2+などに配位させた
りして、膜内に超微粒子前駆体を取り込ませる
ことができる。A compound having an anionic group such as [Formula] and one or two long-chain alkyl groups, such as C o H 2o+1 −COO − Na + (6) C o H 2o+1 −SO 4 - Na + (7) When using the one shown in . More specifically, in the chemical structural formula (6) above, n=19 is sodium arachidate. For the anionic group-containing amphipathic compound, a counterion-forming compound, ie, a cationic metal salt, is used as an ultrafine particle precursor. in particular
Ni(NO 3 ) 2 , AgNO 3 , Hg(NO 3 ) 2 , etc. are used, and an LB film is created with Ni 2+ , Ag + , Hg 2+ as counterions instead of Na + . By reducing these counterions, ultrafine particles of Ni, Ag, and Hg can be obtained. In addition, as the method of incorporation, as shown in the chemical structural formulas (11) and (12) below, amphiphiles that incorporate Pt and Cr components as ultrafine particle precursors into hydrophilic groups through coordinate bonds. using sexual compounds, Alternatively, a ligand having a hydrophilic group such as an ethylenediamine moiety or a bipyridine moiety as shown in the chemical structural formulas (13) and (14) below and two long-chain alkyl groups R, that is, a ligand having coordination ability. Ultrafine particle precursors can be incorporated into the membrane by coordinating amphiphilic compounds with Cu 2+ , Ni 2+ , etc.
【式】【formula】
【式】
さらに、前記取り込ませ方法としては、下
記化学構造式（15），（16）に示されるような両
親媒性化合物それ自身を超微粒子前駆体として
用いるものである。
但し、これら化合物は水に接触すると加水分解
するため、LB膜として水面上に展開できないた
め、蒸着手段などでLB膜様薄膜とする。このよ
うにして調製された製膜を種々の雰囲気で熱分解
することにより酸化物、窒化物、炭化物などの超
御粒子を得ることができる。
製膜技術としては、前記したLB膜製造装置に
よる方法に限定されず、化学修飾法、蒸着法、あ
るいは溶液からの溶媒の蒸発によつて膜が生成
し、結果としてLB膜のような構造を有する膜が
できるのであればその製膜法に限定されるもので
はない。
薄膜を形成させる下地基板については、LB膜
では平滑なものが望ましいが蒸着法、溶媒蒸発法
などでは制約が少なく粉体、多孔質材料、微粒子
でもよい。またその材質としては有機高分子材
料、各種無機材料、金属、炭素などの導体、ある
いは各種半導体、絶縁物など、各種のものを用い
ることができる。
また、LB膜あるいはLB膜様薄膜内に取り込ま
れた超微粒子前駆体を超微粒子に転化する、いわ
ゆる超微粒子形成反応には、還元法、酸化法、沈
殿法、光化学反応、熱分解法など、従来の微粒子
生成反応を利用することができる。例えば酸化還
元反応にあつては気相中、液相中の各種酸化剤、
還元剤が利用できるばかりでなく、下地基板材料
との反応、あるいは下地基板材料を電極として利
用し電気化学的な酸化還元反応を行なわしめても
よい。
なお、前記した（超微粒子前駆体の取り込ませ
方法の（）の項参照）H2PtCl6水溶液上で
LB膜を形成したものは、対イオンとしてLB膜内
に取り込まれたPtCl-- 6を、水素、ヒドラジンな
どの還元剤を用いて還元すると、白金の超微粒子
をLB膜内に形成させることができる。
本発明になる超微細粒子の製造法は、各種の触
媒、例えば前記した白金の場合、電極上に白金の
超微粒子を担持させて燃料電池の電極触媒を製作
する時に有用であり、その場合、触媒活性を低下
させることなくPtを極めて均一に、かつ薄く担
持させることができる（10nｇ／cm2のオーダまで
正確にコントロールできる）ので経済的である。
即ち、白金（Pt）量が従来の1/100量でも同等の
触媒活性が維持される。
その他、本発明になる超微粒子製造法は、超微
粒子をベースとしたエレクトロニクス材料、フア
インセラミツクス材料などの新素材を開発する上
できわめて有用なものである。
次に、本発明になる超微粒子製造法の実施例を
示すが、本発明の技術的思想を逸脱しない限り、
本発明はこれら実施例に限定されるものではな
い。
（実施例）
() 超微粒子前駆体を電気化学的還元法により
超微粒子とする例
グラシーカーボン（glassy Carbon，GC）
の板（60×20×２mm）上に、0.03ｍＭ
H2PtCl6水溶液上に展開したDODAC（前述した
化学構造式(2)においてｎ＝18のもの）の単分子
膜を35dyne／cmの一定表面圧で積層した。こ
のLB製膜プロセスにおいて、GC板を水中から
上昇させる時のみ膜がGC基板上に移し取られ、
いわゆるＺ累積膜となる。
４回浸漬引上げを行なつたGC板を作用電極、
また未処理のGC板電極を対極として、0.1M
H2SO4水溶液中において飽和甘コウ電極に対
し市販のポテンシオスタツトにより50ｍＶ／Ｓ
の掃引速度で＋0.7Vから−0.3Vまで電位掃引
した。これによりLB膜中のPtCl6 -イオンは全
て還元され、白金（Pt）超微粒子に転化した。
その平均粒径は、白金粒子上の水素吸着波と担
持量から40Å以下であることが算出できた。
なお、白金超微粒子の析出量は、LB膜の積
層数（層数）に比例することがその還元電気量
から判明し、その析出量は１層当り50nｇ／cm2
であつた。
また、透過電子顕微鏡による観察のため、別
途、カーボン蒸着膜上において同様な電気化学
的還元法により白金超微粒子を調製したとこ
ろ、その直径は40Åであつた。
() 超微粒子前駆体を化学的還元法により超微
粒子とする例
スライドカラス（76×26×１mm）上に、アセ
チルセルロース膜を貼り、その上にカーボンを
蒸着し、次いで前記（）と同様にしてPtCl6 -
を対イオンとして取り込んだＺ累積膜を調製し
た。このものを10％NaBH4（水素化ホウ素ナト
リウム）水溶液中に１分間浸漬して、PtCl6 -を
還元処理し、その後蒸留水で充分に洗浄した。
アセチルセルロース膜を酢酸メチルで溶解除去
し、残つたカーボン薄膜を透過電子顕微鏡で観
察したところ、白金超微粒子の直径が50Å以下
であつた。
なお、前記実施例において白金（Pt）超微粒
子の生成過程を図式化すると第１図のようにな
る。
第１図において、１は下地基板（GC板）を、
２は対イオンのPtCl- 6−を、３は両親媒性化合物
で、０は親水性部位を、〓は疎水性部位を、４は
Cl-を、またPtは還元反応によりLB膜内に生成さ
れた白金（Pt）超微粒子を、それぞれ示す。[Formula] Furthermore, the incorporation method uses an amphipathic compound itself as shown in the following chemical structural formulas (15) and (16) as an ultrafine particle precursor. However, since these compounds hydrolyze when they come into contact with water, they cannot be developed as an LB film on the water surface, so they are made into an LB film-like thin film by vapor deposition or the like. Super particles such as oxides, nitrides, and carbides can be obtained by thermally decomposing the film thus prepared in various atmospheres. Film forming techniques are not limited to the method using the LB film manufacturing apparatus described above, but films can be formed by chemical modification methods, vapor deposition methods, or evaporation of solvents from solutions, resulting in a structure like an LB film. The film forming method is not limited as long as it can produce a film having the following properties. Regarding the base substrate on which the thin film is formed, a smooth substrate is desirable for LB films, but there are fewer restrictions for vapor deposition methods, solvent evaporation methods, etc., and powders, porous materials, or fine particles may be used. Further, various materials can be used as the material, such as organic polymer materials, various inorganic materials, conductors such as metals and carbon, various semiconductors, and insulators. In addition, the so-called ultrafine particle formation reaction that converts the ultrafine particle precursor incorporated into the LB film or LB film-like thin film into ultrafine particles includes a reduction method, an oxidation method, a precipitation method, a photochemical reaction, a thermal decomposition method, etc. Conventional particulate production reactions can be used. For example, in the case of redox reactions, various oxidizing agents in the gas phase and liquid phase,
Not only can a reducing agent be used, but also an electrochemical redox reaction may be performed by reacting with the underlying substrate material or by using the underlying substrate material as an electrode. In addition, on the H 2 PtCl 6 aqueous solution described above (see section () of the method for incorporating ultrafine particle precursors),
For those that have formed an LB film, ultrafine platinum particles can be formed within the LB film by reducing PtCl -- 6 incorporated into the LB film as a counterion using a reducing agent such as hydrogen or hydrazine. can. The method for producing ultrafine particles according to the present invention is useful when manufacturing an electrode catalyst for a fuel cell by supporting various catalysts, such as platinum as described above, on an electrode. It is economical because Pt can be supported extremely uniformly and thinly without reducing the catalytic activity (it can be precisely controlled down to the order of 10 ng/cm 2 ).
That is, even if the amount of platinum (Pt) is 1/100 of the conventional amount, the same catalytic activity is maintained. In addition, the method for producing ultrafine particles according to the present invention is extremely useful in developing new materials such as electronic materials and fine ceramic materials based on ultrafine particles. Next, an example of the ultrafine particle manufacturing method according to the present invention will be shown, but unless it deviates from the technical idea of the present invention,
The present invention is not limited to these examples. (Example) () Example of converting ultrafine particle precursor into ultrafine particles by electrochemical reduction method Glassy Carbon (GC)
0.03mM on the board (60 x 20 x 2mm)
A monomolecular film of DODAC (n=18 in the chemical structural formula (2) described above) developed on an aqueous H 2 PtCl 6 solution was laminated at a constant surface pressure of 35 dyne/cm. In this LB film forming process, the film is transferred onto the GC substrate only when the GC board is lifted out of the water.
This becomes a so-called Z accumulation film. A GC plate that has been immersed and pulled up four times is used as a working electrode.
In addition, using an untreated GC plate electrode as a counter electrode, 0.1M
50 mV/S using a commercially available potentiostat against a saturated red electrode in an aqueous H 2 SO 4 solution.
The potential was swept from +0.7V to -0.3V at a sweep speed of . As a result, all the PtCl 6 - ions in the LB film were reduced and converted into ultrafine platinum (Pt) particles.
The average particle size was calculated to be 40 Å or less based on the hydrogen adsorption wave on the platinum particles and the amount of hydrogen supported. In addition, it was found from the amount of reduced electricity that the amount of precipitated ultrafine platinum particles was proportional to the number of laminated layers (number of layers) of the LB film, and the amount of precipitated amount was 50 ng/cm 2 per layer.
It was hot. Further, for observation using a transmission electron microscope, ultrafine platinum particles were separately prepared on a carbon-deposited film by a similar electrochemical reduction method, and the diameter was 40 Å. () An example of converting an ultrafine particle precursor into ultrafine particles by chemical reduction. A cellulose acetate membrane was pasted on a glass slide (76 x 26 x 1 mm), carbon was vapor-deposited on it, and then the same procedure as in () above was carried out. PtCl 6 -
A Z-cumulative membrane was prepared in which Z was incorporated as a counter ion. This product was immersed in a 10% NaBH 4 (sodium borohydride) aqueous solution for 1 minute to reduce PtCl 6 - , and then thoroughly washed with distilled water.
When the acetylcellulose film was dissolved and removed with methyl acetate and the remaining carbon thin film was observed with a transmission electron microscope, the diameter of the ultrafine platinum particles was 50 Å or less. Incidentally, the process of producing ultrafine platinum (Pt) particles in the above example is diagrammed as shown in FIG. 1. In Figure 1, 1 is the base substrate (GC board),
2 is the counterion PtCl - 6 -, 3 is an amphipathic compound, 0 is a hydrophilic site, 〓 is a hydrophobic site, 4 is a hydrophobic site.
Cl - and Pt indicate ultrafine platinum (Pt) particles generated within the LB film by a reduction reaction.
第１図は本発明になる白金（Pt）超微粒子の
生成過程を図式化したフローシートである。
１：下地基板（GC板）、２：PtCl-- 6、３：両親
媒性化合物、Ｏ：親水性部位、 Pt ：疎水性部
位、４：Cl-（塩素イオン）、Pt：LB膜内に生成さ
れた白金超微粒子。
FIG. 1 is a flow sheet illustrating the production process of ultrafine platinum (Pt) particles according to the present invention. 1: Base substrate (GC board), 2: PtCl -- 6 , 3: Amphiphilic compound, O: Hydrophilic site, Pt: Hydrophobic site, 4: Cl - (chlorine ion), Pt: in LB film The generated ultrafine platinum particles.
Claims (1)
体を超微粒子に転化して調製したことを特徴とす
る超微粒子。 ２ 下地基材上にLB膜あるいはLB膜様薄膜を形
成するに際して、超微粒子前駆体を同時に膜内に
取り込ませ、ついでLB膜内あるいはLB膜様薄膜
内において前記超微粒子前駆体を超微粒子に転化
させることを特徴とした超微粒子の製造方法。 ３ LB膜あるいはLB膜様薄膜内で超微粒子前駆
体を超微粒子に転化して調製した超微粒子からな
る触媒。 ４ 超微粒子が白金で構成されるものである特許
請求の範囲第３項記載の触媒。 ５ 触微粒子の触媒特性を燃料電池用電極に適用
したものである特許請求の範囲第３項、または第
４項記載の触媒。[Claims] 1. Ultrafine particles characterized in that they are prepared by converting an ultrafine particle precursor into ultrafine particles within an LB film or an LB film-like thin film. 2. When forming an LB film or an LB film-like thin film on the underlying substrate, an ultrafine particle precursor is simultaneously incorporated into the film, and then the ultrafine particle precursor is converted into ultrafine particles within the LB film or LB film-like thin film. A method for producing ultrafine particles characterized by conversion. 3 A catalyst consisting of ultrafine particles prepared by converting an ultrafine particle precursor into ultrafine particles within an LB film or an LB film-like thin film. 4. The catalyst according to claim 3, wherein the ultrafine particles are composed of platinum. 5. The catalyst according to claim 3 or 4, in which the catalytic properties of catalyst particles are applied to an electrode for a fuel cell.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61021295A JPS62180745A (en) | 1986-02-04 | 1986-02-04 | Ultrafine particle prepared in langmuir-blodgett's film, its production and catalyst consisting thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61021295A JPS62180745A (en) | 1986-02-04 | 1986-02-04 | Ultrafine particle prepared in langmuir-blodgett's film, its production and catalyst consisting thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62180745A JPS62180745A (en) | 1987-08-08 |
| JPH0478340B2 true JPH0478340B2 (en) | 1992-12-10 |
Family
ID=12051152
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61021295A Granted JPS62180745A (en) | 1986-02-04 | 1986-02-04 | Ultrafine particle prepared in langmuir-blodgett's film, its production and catalyst consisting thereof |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS62180745A (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01192108A (en) * | 1988-01-27 | 1989-08-02 | Marcon Electron Co Ltd | Manufacture of capacitor |
| JP2708457B2 (en) * | 1988-03-31 | 1998-02-04 | 沖電気工業株式会社 | Ultrafine particle array LB film and method for producing the same |
| JP2004067703A (en) | 2002-04-24 | 2004-03-04 | Japan Science & Technology Corp | Cross-linked polymer, fine particle and method for production |
| KR100449820B1 (en) | 2002-07-02 | 2004-09-22 | 오재완 | The continuous metal powder fabric apparatus with a screw |
| EP1857180B1 (en) * | 2005-02-28 | 2013-05-08 | Nippon Sheet Glass Company, Limited | Noble metal fine particle support and method of manufacturing the same |
| TWI380988B (en) * | 2009-12-31 | 2013-01-01 | Univ Nat Cheng Kung | Platinum complex and methods for making platinum complex and platinum catalyst therethrough |
-
1986
- 1986-02-04 JP JP61021295A patent/JPS62180745A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS62180745A (en) | 1987-08-08 |
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