Strong p‐d Orbital Hybridization on Bismuth Nanosheets for High Performing CO 2 Electroreduction

Abstract Single‐atom alloys (SAAs) show great potential for a variety of electrocatalytic reactions. However, the atomic orbital hybridization effect of SAAs on the electrochemical reactions is unclear yet. Herein, the in situ confinement of vanadium/molybdenum/tungsten atoms on bismuth nanosheet is shown to create SAAs with rich grain boundaries, respectively. With the detailed analysis of microstructure and composition, the strong p‐d orbital hybridization between bismuth and vanadium enables the exceptional electrocatalytic performance for carbon dioxide (CO 2 ) reduction with the Faradaic efficiency nearly 100% for C1 products in a wide potential range from −0.6 to −1.4 V, and a long‐term electrolysis stability for 90 h. In‐depth in situ investigations with theoretical computations reveal that the electron delocalization toward vanadium atoms via the p‐d orbital hybridization evokes the bismuth active centers for efficient CO 2 activation via the σ‐donation of O‐to‐Bi, thus reduces protonation energy barriers for formate production. With such fundamental understanding, SAA electrocatalyst is employed to fabricated the solar‐driven electrolytic cell of CO 2 reduction and 5‐hydroxymethylfurfural oxidation, achieving an outstanding 2,5‐furandicarboxylic acid yield of 90.5%. This study demonstrates a feasible strategy to rationally design advanced SAA electrocatalysts via the basic principles of p‐d orbital hybridization.