JPS59127372A - Electrode for fuel cell - Google Patents

Abstract

PURPOSE:To obtain a high mechanical intensity electrode for a fuel cell from which a catalyst is not separated and in which no cracks are caused and a high performance is maintained over a long period by adding a fibrous substance to make a catalyst layer. CONSTITUTION:A catalyst principally consisting of one or more platinum group elements is supported on a porous conductive carrier such as active carbon, furnace black, graphite powder or the like so that mixture of a given concentration of the catalyst is prepared. After a fibrous substance is added to the carrier catalyst powder, a sufficient amount of water is added to the mixture before it is kneaded to prepare a paste. The thus prepared paste, after being sufficiently mixed, is combined with colloidal polytetrafluoroethylene used as a binder before being kneaded again. The thus prepared paste is applied to a porous conductive base material before this is dried and sintered, thereby obtaining an electrode for a fuel cell. As the fibrous substance, polytetrafluoroethylene also used as the binder can be used since it resists a sintering temperature of 200- 300 deg.C and any substances which can not be activated by electrolyte, fuel and an oxidizing agent may be used. For example glass wool, silica wool, silica, alumina wool, alumina-wool, acid-proof metal wools of tantalum and the like and carbon wool can be used.

Description

【発明の詳細な説明】 〔発明の利用分野〕 本発明は、燃料電池用電極に係り、特に液体燃料を直接
用いる燃料電池において、導電性多孔質基材と、この一
方の表面、あるいは両表面に形成された触媒層とから成
る電極を用いる時、この電極が実用的に形状を保持し、
強度を有する長寿命であるための新規な構成に関するも
のである。[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to an electrode for a fuel cell, and in particular, in a fuel cell that directly uses liquid fuel, the present invention relates to an electrode for a fuel cell, and in particular, a conductive porous substrate and one or both surfaces thereof. When using an electrode consisting of a catalyst layer formed on
The present invention relates to a novel structure for having strength and long life.

〔従来技術〕[Prior art]

燃料を供給し、電極上で電気化学的に燃料を酸化し、直
接電気エネルギー全項り出す燃料電池は古くから研究さ
れてきた。最近、エネルギー源の多様化、燃料の多様化
が進む中で、燃料電池の実用化が多くの研究者によって
進められ、注目を果めている。近い将来に実用化段階に
入るものとして、リン酸を電解質とする酸素・水素燃料
電池がある。これは比較的大きな発電システムとして有
効である。一方、可般用小型発電装置として従来ツエン
ジン発電機に代るものとしてメタノールを直接燃料とし
て用いる燃料電池も有効なものと考えられる。Fuel cells, which supply fuel, oxidize it electrochemically on electrodes, and directly extract all electrical energy, have been studied for a long time. Recently, with the diversification of energy sources and fuels progressing, many researchers are promoting the practical application of fuel cells, and they are attracting attention. An oxygen/hydrogen fuel cell that uses phosphoric acid as an electrolyte is one that will enter the practical stage in the near future. This is effective as a relatively large power generation system. On the other hand, a fuel cell that uses methanol directly as a fuel is also considered to be an effective alternative to the conventional twin-engine generator as a portable small power generator.

燃料電池の基本的構成は、２枚の電極板と、この電極間
に設けられた電解質層から成っている。The basic structure of a fuel cell consists of two electrode plates and an electrolyte layer provided between the electrodes.

電極は、それぞれ導電性多孔質基材、例えば、白金、金
、タンタル、炭素質等の網状もしくは布状の暴利と、こ
の基材上に１種以上の白金族元素を主成分とする触媒、
あるいは、上記触媒を導電性多孔質担体、例えば、活性
炭、グラファイト、ファーネスブラック等の炭素質担体
上に担持した触媒を塗布結着した触媒層とから成ってい
る。燃料電池に燃料が供給さハると、電極上の触媒層に
おいて、燃料および酸化剤は、電気化学的に反応し、こ
れに伴う電極間の物質移動は電解質を介してイオンの移
動として起る。また反応に伴う電気エネルギーは、導電
性基材全弁して外部回路にとり出される。ここで特に酸
性電解質、例えば硫酸水溶液などを用い、メタノールを
直接燃料とする燃料電池においては、燃料極は、液体燃
料と液状電解質が接する電極であり、他方の電極は、液
状の電解質と酸化ｎ（１、例えば酸素や空気の様な気体
とが接触するガス電極である。従来電極は、１種以上の
白金族元素を主成分とする触媒粉末あるいは、１種以上
の白金族元素を主成分とする触媒を、導電性多孔質担体
上に担持した粉末に分散性の結着剤、例えばコロイド状
ポリテトラフルオロエチレンなどを混合しペースト状と
し、これを暴利上に塗布して、乾燥後２００〜３２０Ｃ
の温度で焼成して調製されている。The electrodes each include a conductive porous base material, for example, a net-like or cloth-like material made of platinum, gold, tantalum, carbonaceous material, etc., and a catalyst containing one or more platinum group elements as a main component on this base material.
Alternatively, the catalyst layer may include a catalyst layer in which the catalyst is coated and bound on a conductive porous carrier, for example, a carbonaceous carrier such as activated carbon, graphite, or furnace black. When fuel is supplied to the fuel cell, the fuel and oxidant react electrochemically in the catalyst layer on the electrode, and the associated mass transfer between the electrodes occurs as ion movement through the electrolyte. . Further, the electrical energy accompanying the reaction is taken out to an external circuit through the conductive base material. In particular, in a fuel cell that uses an acidic electrolyte, such as an aqueous sulfuric acid solution, and directly uses methanol as fuel, the fuel electrode is the electrode where the liquid fuel and the liquid electrolyte are in contact, and the other electrode is the electrode where the liquid electrolyte and the oxidized n (1. For example, it is a gas electrode that comes into contact with a gas such as oxygen or air. Conventional electrodes are catalyst powders whose main component is one or more platinum group elements, or catalyst powders whose main component is one or more platinum group elements. A dispersible binder, such as colloidal polytetrafluoroethylene, is mixed with a powder of a catalyst supported on a conductive porous carrier to form a paste, and this is applied onto a surface of a paste and dried for 200 minutes. ~320C
It is prepared by firing at a temperature of .

ここで結着剤として用いられるポリテトラフルオロエチ
レンはそれ自身不活性で、酸性水溶液には濡れないので
、メタノール燃料電池の酸素極の構成利料として重要で
あシ、またメタノール極においても、メタノールの酸化
に伴って発生する炭酸ガスの脱離の促進に対しても有効
なものである。Polytetrafluoroethylene, which is used as a binder here, is itself inert and does not get wet with acidic aqueous solutions, so it is important as a component of the oxygen electrode of methanol fuel cells. It is also effective in promoting the elimination of carbon dioxide gas generated with the oxidation of carbon dioxide.

この様な方法で調製され′ｆｃ電極は性能も優れており
、少量の触媒で、実用に供し得る電池出力を与え有効な
方法といえる。しかしながらこの電極を用いて燃料電池
を組み立てたり、燃料電池を運転すると、触媒層が基材
から剥離しｆｃシ、触媒層構成粒子が脱離する現象が起
り、燃料電池の出力が得られなかったり、長時間、の運
転に伴い出力の低下が生ずる等の問題があった。基材と
の結着力、触媒粉体間の結着力は、結着剤の量を増加す
ると大きくなるが、用いられる結着剤は、上記した撥水
剤（水浴液に濡れない性質）としての機能をもたせてお
り、一般に電気抵抗が太きいために、電極の電気抵抗が
大きくなる。さらには、電極調製工程において、触媒お
よび結着剤をペースト状として塗布するが、これを乾燥
する工程で触媒層の収縮が起シ、ヒビけ」れを生ずる。The 'fc electrode prepared by this method has excellent performance, and can be said to be an effective method that provides a practically usable battery output with a small amount of catalyst. However, when assembling a fuel cell or operating a fuel cell using this electrode, a phenomenon occurs in which the catalyst layer peels off from the base material and the particles constituting the catalyst layer are detached, resulting in a failure to obtain output from the fuel cell. There were problems such as a decrease in output due to long-term operation. The binding force with the base material and the binding force between the catalyst powders increase as the amount of binder increases, but the binder used has the above-mentioned water repellency (property not to get wet with water bath liquid). It has a function and generally has a large electrical resistance, so the electrical resistance of the electrode becomes large. Furthermore, in the electrode preparation process, the catalyst and binder are applied in the form of a paste, but in the process of drying the paste, the catalyst layer shrinks and cracks occur.

このヒビ割れの程厩は用いる触媒粉の性質により異るが
、収縮性の少い基材上に塗布した場合本質的にさけられ
ないものである。このヒビ割れも燃料電池の性能を大き
く低下させるものである。Although the degree of cracking varies depending on the nature of the catalyst powder used, it is essentially unavoidable when coated on a substrate with little shrinkage. These cracks also greatly reduce the performance of the fuel cell.

〔発明の目的〕[Purpose of the invention]

本発明の目的は、上記した従来技術の問題点を解決し、
電極上から触媒が剥ｈ１ｔすることなく、かつヒビ割れ
のない、高強度で長時間に恒って高性能を維持する燃料
電池用電極を提供することにある。The purpose of the present invention is to solve the problems of the prior art described above,
It is an object of the present invention to provide an electrode for a fuel cell that has high strength and maintains high performance for a long time without peeling off the catalyst from the electrode and without cracking.

〔発明のｇ要〕[Key points of invention]

上記目的のため発明者らは、鋭意検討′！ｉｌ−重ねた
結果、本発明に到達した。以上に本発明を詳に１１に説
明する。For the above purpose, the inventors have made extensive studies! As a result of the il-superposition, the present invention was achieved. The present invention will be explained in detail in 11 above.

本発明は、導電性多孔質薄板状基材上に、１種以上の白
金族元素を主成分とする触媒あるいは、この触媒を多孔
質導電性担体に担持した物質を触媒層として形成する。In the present invention, a catalyst containing one or more platinum group elements as a main component, or a material in which this catalyst is supported on a porous conductive carrier, is formed as a catalyst layer on a conductive porous thin plate-like substrate.

液体燃料を用いる燃料電池用電極において、該触媒層が
繊維状物質を含有することを特徴とするものである。本
発明にょる′電極は、例＆ば以下の様にして調製するこ
とができる。The electrode for a fuel cell using liquid fuel is characterized in that the catalyst layer contains a fibrous material. The electrode according to the present invention can be prepared as follows, for example.

予め多孔質導電性担体、例えば活性炭、７アーネスブラ
ツク、グラファイト粉末等に、１種以上の白金族元素を
主成分とする触媒を所定濃度担持する。担持する方法は
、含浸法、沈着法、混練法等通常触媒調製法に用いられ
るいずれの方法であってもよい。この担体付触媒粉に繊
維状物質全添加しさらにペーストとなるに充分な水を曜
加して混練する。充分に混合した後に結着剤として、コ
ロイド状ポリテトラフルオロエチレンを°添加してさら
に混練する。調製されたペーストを導電性多孔質基材上
に塗布して、これを乾燥した後に焼成すると燃料電池用
゛屯極が得られる。本発明による調！Ａ法は上記した調
製法に限定される事なく、種種の方法で調製される。例
えば変形例として、導電性多孔質基材上に、導電性多孔
質担体と繊維状物質及び結着剤からなる担体層金子め上
記の方法に準じて成形し、その後に担体層に触媒成分を
含浸担持する方法などは、有効な方法である。本発明に
用いられる繊維状物質は、ポリテトラフルオロエチレン
が結着剤として機能するための焼成温度２００〜３００
Ｃに耐え、かつ電解質、燃料、酸化剤に不活性のもので
あればよい。例えばガラスウールシリカウール、シリカ
・アルミナウール、アルミナウール、タンタルその他の
耐酸性金属ウール、炭素ウール等を用いることができる
。特に導電性を有する金属ウール、炭素ウールは好まし
い材料である。繊維の径は、多孔質基材上に形成される
触媒層の厚さにもよるが通常触媒層は１＋ＩＲ以下であ
るので、０．１＋＋＋ｍ以下が良く繊維の強度とコスト
を考慮すると０．０１〜０．１間径が好ましい。A predetermined concentration of a catalyst containing one or more platinum group elements as a main component is supported in advance on a porous conductive carrier such as activated carbon, 7-Arnes black, graphite powder, or the like. The supporting method may be any method commonly used in catalyst preparation, such as impregnation, deposition, and kneading. All of the fibrous material is added to this supported catalyst powder, and sufficient water is added to form a paste, followed by kneading. After thorough mixing, colloidal polytetrafluoroethylene is added as a binder and further kneaded. The prepared paste is applied onto a conductive porous substrate, dried, and then fired to obtain a base electrode for a fuel cell. Key according to the present invention! Method A is not limited to the above-mentioned preparation method, but can be prepared by various methods. For example, as a modification, a carrier layer consisting of a conductive porous carrier, a fibrous material, and a binder is formed on a conductive porous base material according to the above method, and then a catalyst component is applied to the carrier layer. Impregnating and supporting methods are effective methods. The fibrous material used in the present invention is fired at a firing temperature of 200 to 300, in order for polytetrafluoroethylene to function as a binder.
Any material may be used as long as it is resistant to C and is inert to electrolytes, fuels, and oxidizers. For example, glass wool, silica wool, silica/alumina wool, alumina wool, tantalum and other acid-resistant metal wool, carbon wool, etc. can be used. In particular, conductive metal wool and carbon wool are preferred materials. The diameter of the fibers depends on the thickness of the catalyst layer formed on the porous base material, but since the catalyst layer is usually 1 + IR or less, the diameter of the fibers is preferably 0.1+++m or less, considering the strength and cost of the fibers. -0.1 diameter is preferred.

０．１閣以上の径では、触媒粉体への分散が不均一で好
ましくないが、逆に０．０１ｍ径以下の繊維を用いても
本発明の効果は出現する。繊維の長さは、触媒粉の混練
によって切断されるので特に限定はないが、余り長いと
混練に長時間かかり好ましくない。また短い場合には本
発明の効果が顕著にならず最も好ましい範囲は０．１〜
１０ｍである。繊維状物質の添加量は、触媒層の物質に
より最適量はわずかに変化するが、５〜３０重量％の添
加が好ましい。しかしこれは必ずしも限定的ではなく添
加量が少くなると本発明の効果が徐々に少くなり、３０
重量％よりも多くなると、導電性のない繊維状物質を添
加した場合には、電極の抵抗増加が起る。得られたペー
ス）１塗布する寸法ば通常用いられるドクターブレード
法、ローラー圧着法、スクリーン印刷法等を用いたりあ
るいは、／・ケやヘラで塗布することもできる。本発明
に用いられる導電性多孔質基材は、従来用いられてきた
電極用基材を用いることができる。。例えば、耐酸性の
金属金網あるいはエキスパンデッドメタル、メタルスク
リーン等また多孔性炭素板、カーボンクロス、カーボン
繊維不織布等を用いることができる。A diameter of 0.1 m or more is not preferable because the dispersion into the catalyst powder becomes uneven, but on the other hand, even if fibers with a diameter of 0.01 m or less are used, the effects of the present invention can be obtained. The length of the fibers is not particularly limited since they are cut by kneading the catalyst powder, but if the fibers are too long, kneading takes a long time, which is undesirable. In addition, if it is short, the effect of the present invention will not be noticeable and the most preferable range is 0.1~
It is 10m. The optimum amount of the fibrous material to be added varies slightly depending on the material of the catalyst layer, but it is preferably added in an amount of 5 to 30% by weight. However, this is not necessarily limiting, and as the amount added becomes smaller, the effect of the present invention gradually decreases.
If the amount exceeds 1% by weight, the resistance of the electrode will increase if a non-conductive fibrous material is added. If the size of the obtained paste is to be applied, the commonly used doctor blade method, roller pressure bonding method, screen printing method, etc. can be used, or the paste can be applied with a spatula or a spatula. As the conductive porous base material used in the present invention, a conventionally used electrode base material can be used. . For example, acid-resistant metal wire mesh, expanded metal, metal screen, porous carbon plate, carbon cloth, carbon fiber nonwoven fabric, etc. can be used.

本発明に用いられる結着剤は従来用いられて来た結着剤
のいずれを用いても有効であるが、特にポリテトラフル
オロエチレンもしくはその誘導体を用いることは好まし
い。添加量は、触媒層重量当９５〜５０％、好ましくは
５〜２０％である。As the binder used in the present invention, any conventionally used binder is effective, but it is particularly preferable to use polytetrafluoroethylene or a derivative thereof. The amount added is 95 to 50%, preferably 5 to 20%, based on the weight of the catalyst layer.

５％よりも少い添加では結着剤の効果が顕著でなく、５
０％よりも多いと、電極の電気抵抗増加により−Ｅｉ極
性能は低下してしまう。調製時の焼成温度は結着剤の性
質によって異るが、例えばポリテトラフルオロエチレン
あるいはその誘導体では、２００〜３２０Ｃの範囲が好
ましい。またこのポリテトラフルオロエチレンあるいは
その誘導体は、撥水性を有するので、これを予め導電性
多孔質基材のガスと接触する面に塗布して撥水層を形成
したガス電極とする場合にも用いられる。If less than 5% is added, the effect of the binder is not significant;
If it is more than 0%, the -Ei electrode performance will deteriorate due to an increase in the electrical resistance of the electrode. The firing temperature during preparation varies depending on the properties of the binder, but for example, in the case of polytetrafluoroethylene or its derivatives, it is preferably in the range of 200 to 320C. Furthermore, since polytetrafluoroethylene or its derivatives have water repellency, they can also be used to form gas electrodes by coating the surface of a conductive porous base material that will come into contact with gas in advance to form a water repellent layer. It will be done.

本発明によって調製された電極は、触媒層と導電性基材
との結着力が大きくまた触媒層粒子間には、繊維状物質
が介在して結着力を高めると同時に、電極調製時触媒層
の乾燥によるヒビ割れが起らなくなる。こうして得られ
た電極は、燃料α波組立て時の破損もなく、また長時間
運転しても、触媒の脱落がない長時間高性能を維持する
ものである。The electrode prepared according to the present invention has a strong binding force between the catalyst layer and the conductive base material, and a fibrous substance is interposed between the catalyst layer particles to increase the binding force, and at the same time, the binding force between the catalyst layer and the conductive base material is increased. No more cracking due to dryness. The electrode obtained in this way is not damaged during assembly of the fuel alpha wave, and maintains high performance for a long time without the catalyst falling off even after long-term operation.

〔発明の実施例〕[Embodiments of the invention]

以下に実施例によシさらに詳しく説明する。 A more detailed explanation will be given below using examples.

実施例１ 炭素粉末（ファーネスブラック：　ＣＣ８Ｘ１５０Ａ２
）５とこれにＨ４Ｆ　ｔｃ１６１．０５ｇ、　ＲｕＣｔ
３０．５１　ｇ　’にとりこれＨ２Ｏ３００ｍｌ加えテ
攪拌する。　Ｈ２Ｐ　ｔＣ７４トＲ，ｕＣ１３が溶解し
た後に３５％ＨＣＨＯ溶液１５ｍｔ”を添加する。これ
をドライアイス−エタノール冷媒中で攪拌しながら、溶
液を＋２〜−２じに冷却する。この溶液に５０重量％Ｋ
ＯＨ水浴液を約２ｍｔｌ―の速度で添加する。この開成
の温度は＋２へ−−２ｉｃになる様に保持する。添加終
了後溶液を室温にもどしさらに３０〜４０Ｃまで徐々に
昇温し、この温度で約３０沙間攪拌保持して、Ｈ２Ｐ　
ｔ　ＣｔｓとＲＬＩＣ１３を還元する。さらにこの溶液
を５針刈ＯＣで約３０分攪拌した後に固形物を水洗しス
ラリーのｐＨが７以下になるまで洗浄をくり返す。洗浄
後のケーキは真窒乾燥器１００Ｃで充分に乾燥する。乾
燥した固形物は、解砕する。Example 1 Carbon powder (furnace black: CC8X150A2
) 5 and H4F tc161.05g, RuCt
Add 300 ml of H2O to 30.51 g' and stir. After the H2P tC74, uC13 has dissolved, add 15 mt of 35% HCHO solution. While stirring this in a dry ice-ethanol refrigerant, cool the solution from +2 to -2 times. To this solution, add 50% by weight. K
Add the OH water bath at a rate of about 2 mtl. The opening temperature is maintained at +2 to -2 ic. After the addition, the solution was returned to room temperature and then gradually raised to 30-40C, and stirred and maintained at this temperature for about 30 seconds to dissolve H2P.
t Reduce Cts and RLIC13. Further, this solution is stirred for about 30 minutes using a 5-needle OC, and then the solid matter is washed with water, and washing is repeated until the pH of the slurry becomes 7 or less. The cake after washing is thoroughly dried in a true nitrogen dryer at 100C. The dried solids are crushed.

得られた触媒粉末は、炭素を担体とし、Ｐｔ１０Ｍ量％
、ＲＬＩ５重量％含有していた。The obtained catalyst powder used carbon as a carrier and contained 10M% of Pt.
, contained 5% by weight of RLI.

実施例２ 実施例１で得られた触媒粉末０．７５ｇをとり、これに
カーボン繊維（東し製、トレカチップドファイバー長さ
３聰）ｔｏ、１１ｇ添加し乳鉢でＨ２Ｏ２、５ｍ　を加
えてよく混練する。繊維が充分に分散した後コロイド状
テトラフルオロエチレン液（ダイキン工業製ポリフロン
ディスパージョンＤＩ。Example 2 Take 0.75 g of the catalyst powder obtained in Example 1, add 11 g of carbon fiber (manufactured by Toshi, trading card chipped fiber, length 3) to it, and add 5 m of H2O2 in a mortar. Knead. After the fibers were sufficiently dispersed, a colloidal tetrafluoroethylene liquid (Polyflon Dispersion DI manufactured by Daikin Industries, Ltd.) was used.

５倍希釈：テトラフルオロエチレン１２重量％含有）　
’！ｉ＝　０．２　ｍ　Ｌを加えてよく混合する。この
ペースト状物質を５０Ｘ１００ｍｍ　の多孔質カーボン
ペーパ（呉羽化学製、クレカマントＥ７１５）に均一に
塗布する。これを乾燥後、３００Ｃ，窒素気流中で３０
分焼成する。得られた触媒は、白金１．５　ｍ　ｇ／ａ
ｒｔ？　、ルテニウム０．７５ｍｇＡゴ含有しカーボン
ｆＩ１．維ｋ、１５Ｍ量％含有する。これをメタノール
極用電極ｌとした。5-fold dilution: Contains 12% by weight of tetrafluoroethylene)
'! Add i=0.2 mL and mix well. This paste-like substance is uniformly applied to a 50×100 mm porous carbon paper (Kurekamant E715, manufactured by Kureha Chemical Co., Ltd.). After drying this, 300C in a nitrogen stream
Bake separately. The resulting catalyst contained 1.5 mg of platinum/a
rt? , containing 0.75 mg of ruthenium and carbon fI1. Contains 15M amount% of fiber K. This was used as electrode 1 for methanol electrode.

比較例１ 実施例１において得られた触媒粉本０．７５ｇにカーボ
ン繊維を加えない以外は、実施例２と全く同様の方法で
調製した触媒をメタノール極用比較電極１とした。Comparative Example 1 A catalyst prepared in exactly the same manner as in Example 2 except that carbon fiber was not added to 0.75 g of the catalyst powder obtained in Example 1 was used as Comparative Electrode 1 for methanol electrode.

実施例３ 実施例１で調製した触媒粉末０．７５　ｇにシリカアル
ミナウール（イソライト工業製、カオウール）０．１１
ｇ添加した以外は、実施例２と同様にして調製した電極
をメタノール極用電極２とした。Example 3 0.75 g of catalyst powder prepared in Example 1 was added with 0.11 g of silica alumina wool (manufactured by Isolite Industries, Kao Wool).
An electrode prepared in the same manner as in Example 2 except that g was added was used as Electrode 2 for methanol electrode.

実施例４ 実施例１で調製した触媒粉末０．７５　ｇに実施例２で
用いたカーボン繊維ケそれぞれ０．０２３ｇ。Example 4 To 0.75 g of the catalyst powder prepared in Example 1, 0.023 g of the carbon fiber used in Example 2 was added.

０．０３８ｇ、０．０７５ｇ、０．１５ｇ、０．２２ｇ
。0.038g, 0.075g, 0.15g, 0.22g
.

を添加して、実施例２と同様の方法で調製したものを、
メタノール極用電極３，４，５，６，７とした。was prepared in the same manner as in Example 2 by adding
They were designated as methanol electrodes 3, 4, 5, 6, and 7.

実施例５ 実施例１〜４で得られた７種の電極と比較的電極の結着
強＃全比較するために触媒の剥離テストを行った。上記
電極２５Ｘ５０ｍ＋ｎを試験片として切シ出し、これに
巾１２間の接層テープ（住友スリーエム製、スコッチト
ラフティングテープ）を触媒層表向に接着し、次いでこ
のテープを剥ぎ取る。Example 5 A catalyst peeling test was conducted to compare the bonding strength of the electrode with the seven types of electrodes obtained in Examples 1 to 4. The above electrode 25×50m+n was cut out as a test piece, and a contact tape (Scotch Trafting Tape, manufactured by Sumitomo 3M) having a width of 12 was adhered to the surface of the catalyst layer, and then this tape was peeled off.

この操作のＡｉｌ後の電極重量の変化を剥離量として、
そのＭｔ比収した。結果を第１表に示す。比較例１電極
は、触媒層が多量に剥離する。またテスト前の比Ｊ授ト
・す電極には多数の亀裂が観測され、一部には亀裂をノ
出して基材が観察された。一方メタノール極用１電極Ｉ
″ｉ、融媒層懺聞に亀裂は全く観測されず、剥離テスト
による触媒の剥離量は、比較例電極のそれに幻して約１
／１ｏ以下でめった。またメタノール極用２についても
剥離量は著しく減少している。The change in electrode weight after Ail in this operation is taken as the amount of peeling,
The Mt specific yield was calculated. The results are shown in Table 1. In the electrode of Comparative Example 1, a large amount of the catalyst layer peels off. In addition, many cracks were observed in the electrode before the test, and in some cases, cracks were observed in the base material. One electrode I for methanol electrode
``i, No cracks were observed in the melting medium layer, and the amount of catalyst peeled off in the peel test was about 1
Rarely below /1o. Furthermore, the amount of peeling was significantly reduced for methanol electrode 2 as well.

メタノール他用３〜７電極では、添カロした繊維の墓を
変えたものである。３重量％添加電極は、触媒層表向に
わずか亀裂が観測されるが、剥離は少くなっている。剥
離量は繊維添加量の増加とともに減少し、添加量５重量
％以上で顕著なことが解る。以上の結果から、本発明に
よる電極では、触媒層表面に亀裂のない、結ン旨力の大
きい触媒層を有する電極でおることが解る。In the 3rd to 7th electrodes for methanol and other uses, the structure of the added fibers was changed. In the electrode containing 3% by weight, slight cracks were observed on the surface of the catalyst layer, but there was less peeling. It can be seen that the amount of peeling decreases as the amount of fiber added increases, and becomes noticeable when the amount added is 5% by weight or more. From the above results, it can be seen that the electrode according to the present invention has a catalyst layer with a high binding power and no cracks on the surface of the catalyst layer.

実施例６ 炭素粉末（キャボット社製、パルカンＸＣ７２Ｒ，）０
、５０　ｇをとシこれに実施例２で用いたカーボン繊維
０．０７５　ｇ添加し実施例２と同様の方法で調製した
ペースト？、実施例２で用いた５　０Ｘ　１００ｒｎｍ
のカーボンベーパの一方の面を予めコロイド状ポリテト
ラフルオロエチレン添着量が１．５　ｍ　ｇｌｔ−とな
る様に塗布し乾燥した暴利の他方の間に塗布した。これ
を乾燥後、全気中３００Ｃで約３０分ＩＨＪ焼成した。Example 6 Carbon powder (manufactured by Cabot, Palkan XC72R,) 0
A paste was prepared in the same manner as in Example 2 by adding 0.075 g of the carbon fiber used in Example 2 to this paste. , 50X 100rnm used in Example 2
One side of the carbon vapor was coated in advance so that the amount of colloidal polytetrafluoroethylene impregnated was 1.5 mg glt-, and then it was coated between the other side of the dried carbon vapor. After drying, it was IHJ fired at 300C in full air for about 30 minutes.

次いでＨ４Ｆ　ｔｃｚａ　ｏ、　１１　ｇ　ｆ　１．５
ｍ　ｌのエタノールに溶液した液を上記板状成形物の炭
素粉本塗布向に含浸し、１００Ｃ％空気中で乾燥する。Then H4F tcza o, 11 g f 1.5
ml of a solution in ethanol is impregnated onto the carbon powder coating side of the plate-shaped molded article, and dried in 100C% air.

これを、水、エタノール１：１種合液に１０重搬％Ｎａ
ＢＨ４を溶解した液に２〜３分浸漬し、こ′ｔ′Ｌヲ取
シ出し、充分に水洗した後に８０Ｃ１空気中で１０時間
乾燥し、空気極用電極８とした。Add this to a 1:1 mixture of water and ethanol with 10% Na
It was immersed in a solution in which BH4 was dissolved for 2 to 3 minutes, the L was taken out, thoroughly washed with water, and then dried in 80C1 air for 10 hours to obtain an electrode 8 for an air electrode.

比較例２ 実Ｆ１６において、用いたカーボン繊維を添加しない以
外は、実施例６と同様の方法で調製した電極を空気極用
比較電極２とした。Comparative Example 2 An electrode prepared in the same manner as in Example 6 in the actual F16 except that the carbon fiber used was not added was used as a comparative electrode for air electrode 2.

実施例７ 実力山側６及び比較例２で得られた電極を２５Ｘ１００
ｍに切シ出し、これを実施例５と同様の方法で剥離テス
トを行った、結果を第２表に示す。Example 7 The electrodes obtained in the actual peak side 6 and comparative example 2 were
A peel test was performed using the same method as in Example 5. The results are shown in Table 2.

比４メ砦極２に比べ空気他用電極８の剥離量が少く、強
度が大きいことが解る。It can be seen that the amount of peeling of the electrode 8 for air etc. is smaller than that of the 4-metre electrode 2, and the strength is greater.

実施例 実施レリ２で併ら７したメタノール極用電極２と実施例
７で得られた箪気極用電極８全５０Ｘ５０ｉｉに切シ出
し、こ′Ｊ″Ｌを用いて第１の革電池を構成した。EXAMPLE Cut out the methanol electrode 2 and the small gas electrode 8 obtained in Example 7 into 50 x 50 ii pieces, and use this 'J''L to make a first leather battery. Configured.

！、た比較例１で得られたメタノール極用電極と比較例
２で得られた空気極用電極を５０Ｘ５０ｍ＋ｎに切り出
し、これを用いて第２の単セルケ構成した。! The methanol electrode obtained in Comparative Example 1 and the air electrode obtained in Comparative Example 2 were cut into 50×50 m+n pieces, and used to construct a second single cell.

それぞれのセルにおいて１対の′磁極間には、３ｍｏ　
ｔ／　ｌ　Ｈ２Ｓ　０４に浸漬した陽イオン交換膜（デ
ュポン製、ナフィオン）を電解質として介在させた。In each cell, between a pair of magnetic poles, 3 mo
A cation exchange membrane (DuPont, Nafion) soaked in t/l H2S04 was interposed as an electrolyte.

明化剤は空気、燃料は１ｍ０Ａ／７　ＣＨ３０Ｈと３ｍ
０１７Ｌ　Ｈ２８０４ｋ含有する溶液を用い、それぞれ
電池外部よシフアン及びポンプで連続的に供給した。Brightening agent is air, fuel is 1m0A/7 CH30H and 3m
A solution containing 017L H2804k was used, and was continuously supplied from outside the battery using a pump and a pump.

電池の運転温度は６０Ｃに保持した。初期の田力は電流
密度６０ｍνｄで、第１の単セルＵ０．４０■、第２の
単セルは０．４３Ｖであった。これを各１０時間毎に燃
料供給を停止する操作をくり返して２００時間運転した
ところ、第１の単セル電圧は０．３３ＶＸ第２の単セル
電圧は０．４２Ｖであった。The operating temperature of the battery was maintained at 60C. In the initial stage, the current density was 60 mvd, the first single cell U0.40V, and the second single cell U0.43V. When this operation was repeated for 200 hours by repeatedly stopping the fuel supply every 10 hours, the first single cell voltage was 0.33V, and the second single cell voltage was 0.42V.

第　　　　　１　　　　　表 第　　　　２　　　　衣 日立市幸町３丁目１番１号株式 ％式％ 日立市幸町３丁目１番１号株式 会社日立製作所日立研究所内Chapter 1 Table Part 2 Clothes Hitachi City Saiwaicho 3-1-1 Stock %formula% Hitachi City Saiwaicho 3-1-1 Stock Hitachi Research Institute, Hitachi, Ltd.

Claims (1)

【特許請求の範囲】 １、導電性多孔質薄板状基材と該基材上に１種以上の白
金族元素を主成分とする触媒物質、あるいは該触媒物質
を導伝性多孔質相体に担持せしめた物質を含有する触媒
層を形成してなる液体燃料を用いる燃料電池用電極にお
いて、該触媒層が繊維状物質を苫・可することを特徴と
する燃料電池用電極。 ２、特許請求の範囲第１項において、繊維状物質が導電
性を有することを特徴とする燃料′電池用電極。 ３、特許請求の範囲第２項において、燃料電池用電解質
として敵性電解質を用いることを特徴とする燃料電池用
電極。 ４、特許請求の範囲第３項において、導電性繊維状物質
が、触媒層重量当り５〜３０％含有すること全特徴とす
る燃料電池用電極。[Scope of Claims] 1. A conductive porous thin plate-like base material and a catalytic material containing one or more platinum group elements as a main component on the base material, or the catalytic material is formed into a conductive porous phase. 1. An electrode for a fuel cell using a liquid fuel formed by forming a catalyst layer containing a supported substance, characterized in that the catalyst layer absorbs a fibrous substance. 2. The electrode for a fuel cell according to claim 1, wherein the fibrous material has electrical conductivity. 3. A fuel cell electrode according to claim 2, characterized in that a hostile electrolyte is used as the fuel cell electrolyte. 4. The electrode for a fuel cell according to claim 3, characterized in that the conductive fibrous material is contained in an amount of 5 to 30% based on the weight of the catalyst layer.