Au-modified PtCu nanodendrites as a highly stable and active electrocatalyst.

Direct galvanic replacement of surface Cu with Au 3+ in PtCu 3 nanodendrites is applied to synthesize an Au-modified PtCu 3 nanodendrite catalyst (PtCu 3 -Au), which shows both superior stability and excellent activity for the methanol oxidation reaction (MOR) and oxygen reduction reaction (ORR). The PtCu 3 -Au catalyst only lost 7% of its MOR activity and its ORR half-wave potential decreased 8 mV after 10 000 potential cycles.