摘要 |
Catalysts contain noble metal-containing particles that has a composition except oxygen represented by a formula PtXRuYAZSnS and exhibits a mean particle diameter of from 0.5 nm to 10 nm, both inclusively. A is at least one element selected from a group consisting of Rh, Au, Pd, Ir and Os, and X, Y, Z and S are atomic ratios satisfying relations 30<=X <=70, 30<=Y<=70, 0<=Z<=40, 0.5<=S<=8 and X+Y+Z+S=100. |