Activity and Structure of Dealloyed PtNi3 Nanoparticle Electrocatalyst for Oxygen Reduction Reaction in PEMFC

Here, we report a synthesis and activity study of the dealloyed, highly active PtNi3 alloy nanoparticle catalyst for the oxygen reduction reaction (ORR). The dealloyed PtNi3 exhibits 7 - 8 times higher Pt mass based activity and 6 - 7 times higher Pt surface area specific based activity for ORR than pure Pt by similar mean particle size. Further, we have tested the long-term durability of the dealloyed PtNi3 for the typical and corrosive operating fuel cell conditions. After the voltage testing with 10000 voltage cycles between 0.5 - 1.0 V vs. RHE and a scan rate of 50 mV s(-1) in deaerated 0.1 M HClO4 the activated PtNi3 catalyst still shows 4 - 5 fold increase in Pt surface area specific based activity compared with that for pure Pt.