Influence of sputtering parameters on hydrogen evolution overvoltage in sputter-deposited Co-Mo alloy electrode

Sputtering method was used to prepare the Co-Mo alloy electrode for the hyd rogen evolution reaction in water electrolysis. We studied the influence of the sputtering parameters (Ar pressure during deposition, RF power, and su bstrate temperature) on the hydrogen evolution overvoltage. It was found th at the Overvoltage was significantly influenced by the Ar pressure which af fected critically the Co-Mo surface geometrical structure. We referred to t he Thornton model for the microstructure of sputter-deposited films to expl ain the observed structural change. (C) 2001 Elsevier Science B.V. All righ ts reserved.