In electrochemical reactions, interactions between reaction intermediates and catalytic surfaces control the catalytic activity, and thereby require to be optimized. Electrochemical de-alloying of mixed-metals nanoparticles is a promising strategy to...

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Economical production of highly active and robust Pt catalysts on a large scale is vital to the broad commercialization of polymer electrolyte membrane fuel cells. Here, we report a low-cost, one-pot process for large-scale synthesis of single-crystal Pt multipods with abundant high-index facets, in an aqueous solution without any template or surfactant. A composite consisting of the Pt multipods (40 wt %) and carbon displays a specific activity of 0.242 mA/cm2 and a mass activity of 0.109 A/mg at 0.9 V (versus a reversible hydrogen electrode) for oxygen reduction reaction, corresponding to ∼124% and ∼100% enhancement compared with those of the state-of-the-art commercial Pt/C catalyst (0.108 mA/cm2 and 0.054 A/mg). The single-crystal Pt multipods also show excellent stability when tested for 4500 cycles in a potential range of 0.6–1.1 V and another 2000 cycles in 0–1.2 V. More importantly, the superior performance of the Pt multipods/C catalyst is also demonstrated in a membrane electrode assembly (MEA), achieving a power density of 774 mW/cm2 (1.29 A/cm2) at 0.6 V and a peak power density of ∼1 W/cm2, representing 34% and 20% enhancement compared with those of a MEA based on the state-of-the-art commercial Pt/C catalyst (576 and 834 mW/cm2).