Abstract: Disclosed is a platinum alloy catalyst comprising a carbon support and, platinum, manganese and iron supported thereon. The activities of this platinum alloy catalyst are higher than those of a binary alloy catalyst consisting of platinum and manganese and even of a platinum-nickel-cobalt alloy catalyst which is one of the most active conventional platinum alloy catalysts, and its life is greatly extended. Moreover, it is quite useful when utilized as an electrocatalyst of a fuel cell.

Abstract: The polymer solid-electrolyte composition according to the present invention comprises a polymer solid electrolyte selected from the group consisting of perfluorocarbon sulfonic acid, polysulfones, perfluorocarbonic acid, styrene-divinylbenzene sulfonic acid cation-exchange resins and styrene-butadiene anion-exchange resins, and 0.01-50% by weight of fine particle silica and/or fibrous silica fiber relative to the weight of the polymer solid electrolyte.

Abstract: Disclosed herein is a process of preparing a catalyst having narrow particle size distribution and supported with monodispersed metal particles of which a particle size is about less than 20 .ANG.. In the present invention, propargyl alcohol is employed in place of a sulfur-containing agent for supporting the metal particles on a support thereby avoiding the contamination of the sulfur component and the high temperature treatment for decomposing the sulfur-containing agent. Accordingly, the resulting catalyst contains no sulfur contaminant and substantially no agglomerated metal particles.

Abstract: Disclosed herewith is a process of preparing a metal supported catalyst having a high surface area comprising reducing one or more metal-containing ions in a solution employing one or more reducing agents selected from the group consisting of thiourea and thioacetamide, and supporting the reduced metal or metals onto a support. The thiourea and the thioacetamide exhibit more excellent activity and durability than those of ordinary reducing agents such as sodium borohydride and other sulfur-containing reducing agents.

Abstract: Disclosed herein is a process of preparing a catalyst having narrow particle size distribution and supported with monodispersed platinum particles of which a particle size is about less than 20 .ANG.. In the present invention, allyl alcohol and hydrazinc hydrate are employed in place of a sulfur-containing agent for supporting the platinum particles on a support thereby avoiding the contamination of the sulfur component and the high temperature treatment for decomposing the sulfur-containing agent. Accordingly, the resulting catalyst contains no sulfur contaminant and substantially no agglomerated platinum particles.

Abstract: Disclosed is a process of preparing a catalyst supporting highly metal particles comprising, in the presence of carbon monoxide in a solution containing a metal-containing ion and a support on which metal particles produced by reduction of the metal-containing ion are supported, reducing by means of a reductant the metal-containing ion to the corresponding metal particles which are then supported on the support. According to the process of the present invention, because of the presence of the carbon monoxide which is supposed to have a function of depressing the deposition of a new metal particle present around the metal particles supported on the support, that is, the growth of the metal particles and another function of preventing the agglomeration among the metal particles supported, the catalyst of excellent properties having the metal particles supported and monodispersed on the support with the narrow particle size distribution can be prepared of which an average particle size is not more than 20 .ANG..

Abstract: Disclosed is a process of preparing a catalyst supporting highly metal particles comprising, in the presence of ethylene and/or acetylene in a solution containing a metal-containing ion and a support on which metal particles produced by reduction of the metal-containing ion are supported, reducing by means of a reductant the metal-containing ion to the corresponding metal particles which are then supported on the support. According to the process of this invention, because of the presence of the ethylene and/or acetylene which is supposed to have a function of depressing the deposition of new metal particles present around the metal particles supported on the support, that is, the growth of the metal particles and another function of preventing the agglomeration among the metal particles supported, the catalyst of the desired properties can be prepared.

Abstract: Disclosed is an electrocatalyst which comprises an inorganic support and four-element alloy essentially consisting of 10 to 39 atomic percent of platinum, 30 to 5 atomic percent of nickel, 30 to 5 atomic percent of cobalt and 30 to 3 atomic percent of manganese supported on the inorganic support. The electrocatalyst possesses excellent anti-poisoning against carbon monoxide.

Abstract: Disclosed is an electrocatalyst which comprises an inorganic support and a ternary alloy essentially consisting of platinum-palladium-ruthenium supported on the support. The electrocatalyst possesses excellent anti-poisoning against carbon monoxide.

Abstract: Disclosed herein are a platinum alloy catalyst comprising an electroconductive support and platinum-nickel-cobalt alloy particles having an ordered structure supported on the electroconductive support, and a process of preparing the catalyst. The catalyst possesses higher activity and longer durability because of its ordered structure.

Abstract: An electrode for use in a phosphoric acid fuel cell comprising a graphitized or partially graphitized carbon support having a platinum/palladium electrocatalyst thereon. Preferably, the platinum/palladium catalyst comprises 20 to 65 weight percent palladium.

Abstract: Electrocatalyst and hydrophobic polymer particles are combined to form an aqueous suspension which is then applied to a conductive substrate to form an electrode. The colloidal chemistry of the suspension of electrocatalyst particles and hydrophobic polymer particles is controlled prior to the application of the suspension to the substrate such as by the incorporation of a sol of a polyvalent metal oxide or solution of a salt of a polyvalent metal into the suspension.