Electrochemical CO Oxidation and Microstructure in Pt/Co3O4-Based Catalysts

The metal-support interaction in a platinum catalyst supported on cobalt oxide (Pt/Co3O4) was investigated. In the as-calcined catalysts prepared by the impregnation method, platinum particles were highly dispersed on the surface of cobalt oxide with the strong interaction. The as-calcined catalysts were sensitive to the reduction treatment. After the pretreatment with hydrogen, the formation of the intermetallic compound of Pt3Co was observed, accompanied with a significant change in the surface composition and microstructure. Furthermore, the reduced surface species were readily oxidized after exposure to an oxidizing atmosphere. These behaviors were induced by the strong chemical interaction between platinum and cobalt oxide. As a model case study, the electrocatalytic activity for CO oxidation was studied for the applications to polymer electrolyte fuel cells. (C) 2009 The Electrochemical Society. [DOI: 10.1149/1.3129248] All rights reserved.