WC-Supported Ni Single-Atom Catalysts for Efficient Oxygen Evolution Reaction

The oxygen evolution reaction (OER), as the anodic half-reaction of water splitting, is a critical process in renewable energy technologies such as electrolysis and metal-air batteries. However, the sluggish kinetics and poor stability of conventional OER catalysts pose significant challenges. Transition metal-based catalysts, particularly single-atom catalysts, have emerged as promising candidates due to their high atom utilization efficiency and tunable electronic structures. In this study, we present WC-supported Ni single-atom catalysts as a promising solution for efficient OER. Density functional theory (DFT) calculations reveal that WC substrates strongly stabilize Ni single atoms through robust Ni-C interactions, which regulate the charge density of Ni and significantly lower its d-band center. This electronic modification enhances the intrinsic catalytic activity of the Ni-WC system. The introduction of Ni atoms induces lattice distortions in the WC framework, further contributing to the unique electronic structure and improved catalytic performance. Experimental results confirm that the strong bonding between Ni and C within WC ensures exceptional structural stability and prolonged durability under OER conditions. The combination of high activity and stability in the Ni-WC catalyst underscores its potential for practical energy conversion applications. This work provides valuable insights into the rational design of single-atom catalysts and establishes a theoretical and experimental foundation for advancing electrocatalyst development in sustainable energy technologies.