Preparation of an ultrathin Pt electrocatalyst via a galvanic replacement reaction of electrodeposited CuCl for the oxidation of methanol in an alkaline medium.

An ultrathin Pt electrocatalyst is prepared by the electrodeposition of a thin and uniform CuCl semiconductor film on an Au electrode followed by a galvanic replacement reaction with K2PtCl4, which shows an ultrahigh Pt-mass specific electrocatalytic activity of 23.7 mA g(Pt)(-1) for methanol oxidation in an alkaline medium.