Pt0.25Ru0.75/N‐C as Highly Active and Durable Electrocatalysts toward Alkaline Hydrogen Oxidation Reaction

Abstract A series of uniform 3.0–3.8 nm Pt 1− x Ru x particles supported on nitrogen‐doped carbon (N‐C) is synthesized by wet‐impregnation, high‐temperature reduction, and high‐temperature NH 3 etching. As far as it is known, the resultant Pt 0.25 Ru 0.75 /N‐C exhibits the highest activity toward alkaline hydrogen oxidation reaction (HOR) in terms of mass specific exchange current density ( j 0,m , 1654 A g PtRu −1 ), that is 4.7 and 1.4 times of commercial Pt/C (352 A g Pt −1 ) and PtRu/C (1213 A g PtRu −1 ), respectively. The remarkable activity originates from a high electrochemical active surface area (ECSA), weakened hydrogen binding energy (HBE), and appropriate oxophilic property. Additionally, the Pt 0.25 Ru 0.75 /N‐C displays much improved durability during potential cycling with respect to commercial Pt/C and commercial PtRu/C, likely arising from the stabilizing effect of nitrogen dopant of N‐C on Pt 0.25 Ru 0.75 . Furthermore, the single cell fabricated with 0.08 mg Pt cm −2 of the Pt 0.25 Ru 0.75 /N‐C as the anode reaches a peak power density of 831 mW cm −2 , which is 1.8 and 1.1 times of that fabricated with 0.2 mg Pt cm −2 of commercial Pt/C and 0.13 mg Pt cm −2 of commercial PtRu/C as the anode, respectively. This study exhibits that low‐platinum alkaline HOR electrocatalyst should be a highly promising approach for hydroxide exchange membrane fuel cells (HEMFCs).