Mitigating Surface Poisoning by Bidirectional Regulation for Efficient C1‐C2 Molecule Electrooxidation

ABSTRACT The rational design of Pt‐based electrocatalysts to alleviate CO intermediates poisoning during electrooxidation of C1‐C2 fuels (methanol, ethanol, formic acid) presents a grand challenge. Current detoxification strategies predominantly focus on enhancing OH* formation to accelerate CO* oxidation. However, the periodic voltage/current oscillations induced by accumulated OH species are often overlooked. Such accumulation of secondary poisoning intermediates inevitably leads to a high overpotential and poor operational stability. Herein, guided by machine learning screening, we resolve this dilemma by designing ultrathin PtPdGaRuFeMo high‐entropy alloy nanosheets featuring Ga and Ru dual‐promoter sites for the bidirectional regulation of CO* and OH* adsorption. Both theoretical analysis and experimental results demonstrate that the synergistic Ga and Ru sites modulate the electronic structure of active centers, balancing the dynamic adsorption of CO* and OH* to mitigate surface poisoning. Consequently, the as‐prepared catalysts deliver excellent specific activities of 5.4 mA cm −2 for methanol and 3.5 mA cm −2 for formic acid electrooxidation, surpassing commercial Pt/C by factors of 9.7 and 12.8, respectively. This study establishes a dual‐promoter bidirectional regulation, providing a promising route offering a robust solution to the stability‐activity trade‐off in fuel‐cell electrocatalysts.