Synergistic Regulation of Oxygen Reduction Activity on Antimonene via Transition Metal-Nonmetal Dual-Atom Doping

Two-dimensional antimonene has recently emerged as a promising electrocatalytic platform; however, its oxygen reduction reaction (ORR) activity and modulation strategies remain largely unexplored. Herein, density functional theory (DFT) calculations are employed to systematically investigate ORR catalysis on antimonene co-doped with transition metal (TM) and nonmetal (C, P) dual atoms. The results reveal that Pd@C-Sb, Pt@C-Sb, and Pd@P-Sb exhibit remarkably enhanced ORR activity, delivering low overpotentials of 0.31 V, 0.32 V, and 0.38 V, respectively, significantly outperforming their single-atom-doped counterparts. Mechanistic analyses demonstrate that nonmetal dopants induce strong synergistic interactions with TM centers, leading to charge redistribution and effective regulation of the TM d-band center, which optimizes the adsorption energetics of key ORR intermediates. Notably, the number of d-electrons of TM atoms is identified as a reliable electronic descriptor governing intermediate binding strength and catalytic activity. Furthermore, ab initio molecular dynamics simulations confirm the excellent thermodynamic stability of the optimized dual-atom catalysts. This work elucidates the atomic-scale origin of synergistic enhancement in dual-atom-doped antimonene and provides a rational design strategy for high-performance ORR electrocatalysts based on two-dimensional main-group materials.