ABSTRACT Designing high‐efficiency Oxygen evolution reaction (OER) electrocatalysts is hindered by high overpotentials and the reliance on precious metals. To address this, we designed a series of single‐atom catalysts by anchoring transition metal atoms (TM = Co, Ni, Rh, Pd, Ir, Pt) into stable S1 vacancy of TiNbS4 (TM@S1–TiNbS4) and systematically evaluated their catalytic performance using Density functional theory (DFT) calculations. Notably, Ni‐, Rh‐, and Pt‐doped systems exhibited outstanding OER activity, with low overpotentials in the range of 0.45 ∼ 0.51 V, outperforming the benchmark IrO2 catalyst of 0.56 V. We further identified the O* adsorption free energy and the d‐electron number of the TM atoms as effective descriptors for OER. In addition, molecular orbital analysis revealed that the hybridization between TM‐d orbital and O‐ p orbitals (π* antibonding) facilitates appropriate adsorption of oxygen intermediate on the active sites, thereby enhancing OER activity. Furthermore, biaxial strain was utilized to optimize OER performance of representative Rh@S1–TiNbS4, shifting its activity closer to the peak of the volcano plot. Apparently, Rh@S1–TiNbS4 showed the lowest overpotential of 0.40 V under a 2% biaxial tensile strain. This work not only proposes a promising class of single‐atom catalyst for OER but also provides fundamental insights into a practical strain‐engineering strategy for advancing electrocatalytic performance.
Li et al. (Thu,) studied this question.