화학공학소재연구정보센터
Journal of Applied Electrochemistry, Vol.46, No.9, 995-1010, 2016
Methanol electro-oxidation on nanoporous metals formed by dealloying of Ag-Au-Pt alloys
Novel nanoporous structures, with narrow distribution of pore and ligament sizes, were formed by electrochemical dealloying of ternary precursors (Ag-Au-Pt with platinum content of 1, 2, and 3 at.% and 77 at% of silver). These three-dimensional bicontinuous porous network structures proved to be active electrocatalysts for the methanol oxidation reaction. By changing the processing conditions (e.g., dealloying temperature) and/or post-dealloying treatments (e.g., exposure to moderately high temperature in the presence of air) of these structures, the characteristics of the resulting materials were modified (e.g., ligament size and platinum content on the surface of the ligaments) and with that their catalytic response. It was demonstrated that these high surface area nanostructures displayed enhanced specific activity and distinct surface reactivity compared with nanoporous gold formed by dealloying of Ag-Au alloy. Scanning electron microscopy, transmission electron microscopy, and electrochemical methods such as underpotential deposition of hydrogen and cyclic voltammetry were used to characterize the resulting nanoporous structures.