| abstract |
[Problem] To provide a catalyst which is stable and does not corrode at high potentials or in acidic electrolytes of fuel cells, effectively participates in electrode reactions, not only in catalyst particles present on the surface contacting an electrolyte membrane but also at a three-phase interface, of a gas phase (humidified reaction gas) and a liquid phase, formed in catalyst particles in a catalyst layer present in a location far away from the electrolyte membrane, has a high utilization efficiency of catalyst particles, has a high oxygen reduction ability, can achieve high performance, and is inexpensive compared to platinum. A fuel cell thus obtained exhibits high performance, has a long lifetime, and is relatively low-cost and thus has excellent economic efficiency. [Solution] The present invention provides a porous catalyst comprising molybdenum, boron, and a sulfur-containing oxycarbonitride containing the following metal K (at least one metal selected from the group consisting of tantalum, zirconium, copper, iron, tungsten, titanium, vanadium, cobalt, manganese, aluminum, and nickel). |