Structural analysis of polymer-protected pd/rh bimetallic clusters by using exafs spectroscopy

Abstract

The colloidal dispersions of the palladium-rhodium bimetallic clusters, prepared by refluxing the solution of their salts in water/ethanol in the presence of poly(N-vinyl-2-pyrrolidone) under nitrogen, are analyzed by EXAFS spectroscopy, showing that the bond distance between the Pd atom and Rh atom in the cluster is about 2.70 on the basis of the EXAFS measurements of the Pd/Rh alloy foils. The coordination numbers of the Pd/Rh dispersions indicate that the small particles in size mainly consist of Pd/Rh bimetallic clusters and the large particles, of palladium clusters. © 1993 The Japan Society of Applied Physics.