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Breaking atomic monogeneity of catalyst surfaces is promising for constructing synergistic active centers to cope with complex multi‐step catalytic reactions. Here, we report a defect‐derived strategy for creating surface phosphorous vacancies (P‐vacancies) on nanometric Rh2P electrocatalysts toward drastically boosted electrocatalysis for alkaline hydrogen oxidation reaction (HOR). This strategy disrupts the monogeneity and atomic regularity of the thermodynamically stable P‐terminated surfaces. Density functional theory calculations initially verify that the competitive adsorption behavior of Had and OHad on perfect P‐terminated Rh2P{200} facets (p‐Rh2P) can be bypassed on defective Rh2P{200} surfaces (d‐Rh2P). The P‐vacancies enable the exposure of sub‐surface Rh atoms to act as exclusive H adsorption sites. Therein, the Had cooperates with the OHad on the peripheral P‐sites to effectively accelerate the alkaline HOR. Defective Rh2P nanowires (d‐Rh2P NWs) and perfect Rh2P nanocubes (p‐Rh2P NCs) are then elaborately synthesized to experimentally represent the d‐Rh2P and p‐Rh2P catalytic surfaces. As expected, the P‐vacancy‐enriched d‐Rh2P NWs catalyst exhibits extremely high catalytic activity and outstanding CO tolerance for alkaline HOR electrocatalysis, attaining 5.7 and 14.3 times mass activity that of p‐Rh2P NCs and commercial Pt/C, respectively. This work sheds light on breaking the surface atomic monogeneity for the development of efficient heterogeneous catalysts. [ABSTRACT FROM AUTHOR]

Low‐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. [ABSTRACT FROM AUTHOR]

Engineering the surface electrochemistry at the atomic level can precisely and effectively manipulate the reactivity and durability of catalysts. Herein, a novel single‐atom fine‐tailoring strategy based on a highly hydrophilic Mo‐bifunctional promoter is proposed to greatly boost the hydrogen oxidation reaction (HOR) on Pt catalysts. The single‐atom Mo‐modified nanometer Pt anchored on porous N‐doped carbon (Mo‐Pt/NC) is developed via a pyrolysis–adsorption–reduction process. The designed Mo‐Pt/NC exhibits a remarkable mass‐specific kinetic current reaching 1584 mA mg−1Pt in 0.1 m KOH, which is nearly 11‐fold and fourfold higher than the activities of commercial Pt/C and Pt/NC counterparts respectively, and such extraordinary HOR behavior even exceeds those of documented Pt‐related catalysts. Electrochemical and spectroscopic studies indicate that hydrophilic Mo single‐atom sites can not only regulate the electronic microenvironment of Pt sites for attenuated H* adsorption, but they also serve as energetic H2O*‐adsorption promoters to jointly facilitate the HOR kinetics. Moreover, the anti‐CO poisoning capability of Mo‐Pt/NC is markedly enhanced by this Mo‐modified electronic effect. This work gives a significant guideline for the design of high‐performance HOR catalysts and other advanced catalysts. [ABSTRACT FROM AUTHOR]