| 摘要 |
Catalytic material for fuel cell electrodes and composed of Ni, Ag, Mo and Ni-P, is produced by reacting, in aqueous solution, a nickelous salt, a silver salt in a concentration not exceeding 0.55 moles Ag+ per mole Ni++, a molybdenum salt in which the Mo is in an oxidation state of +2 to +6 and in a quantity sufficient to provide 6-8.5% by weight Mo in the final material, a condensed Nicomplexing polyphosphate in a quantity sufficient to prevent precipitation of basic Ni salts, and an alkali metal hypophosphite in a quantity sufficient to reduce the nickelous ions to nickel; the pH of the solution being maintained at at least 10 by addition of hydroxyl ions. The result is a flocculent precipitate consisting, by weight, of .Ni.43.6-78.4% .Ag.6.75-25.4% .Mo.6-8.5% .P.0.6-2.24% .Impurities (e.g. O, N, H) - balance.. Specified reactants are nickel sulphate, silver sulphate, molybdenum trioxide, sodium pyro-phosphate and sodium hypophosphite. Hydroxyl is preferably supplied by NH4OH or alkali metal hydroxide. The solution may be heated to 52 DEG -82 DEG C. The material is formed to shape by sintering at below 850 DEG C; or by mixing with P.T.F.E. and heating; or by making a matte with asbestos fibre. |
