Local Oxidation Induced Amorphization of 1.5‐nm‐Thick Pt–Ru Nanowires Enables Superactive and CO‐Tolerant Hydrogen Oxidation in Alkaline Media

Abstract

AbstractLow‐dimensional amorphous metallic nanomaterials provide great possibility for creating high‐performance electrocatalysts owing to their conspicuous reacting merits derived from the flexible coordination structures, but remain extremely challenging in synthesis. Herein, this work reports a facile synthesis of carbon‐loaded amorphous 1.5‐nm‐thick Pt–Ru nanowires (NWs) through a local oxidation induced amorphization process. During annealing premade crystalline Pt–Ru NWs/C in air, a local‐oxidation of the oxyphilic Ru generates abundant random Ru–O bonds and disturbs the order bimetallic lattices. The as‐prepared amorphous Pt53Ru47 (a‐Pt53Ru47) NWs/C exhibits an extremely high activity (13.7 A mg−1 at 25 mV overpotential) and an excellent CO‐tolerance for alkaline hydrogen oxidation reaction (HOR) electrocatalysis, drastically outperforming the crystalline counterpart and commercial benchmarks. Mechanism studies indicate the Pt–Ru bimetallic effects as well as the rich disordered “Pt–Ru–O” and/or “Pt–O–Ru” atomic heterojunctions can weaken the *H binding energy and inversely strengthen the *OH adsorption, thus promoting the alkaline HOR kinetics. More uniquely, the small interatomic spaces derived from the disordered bond nets present a H2/*H‐selected permeability, which spatially obstruct the relatively larger CO molecules to poison the internal catalytic sites during HOR. The CO‐shielded internal catalytic sites and the enriched surface *OH jointly upgrade the CO‐tolerance of the a‐Pt53Ru47 NWs/C catalysts.