Manipulating the D‐Band Center of Confined Nickel by Lattice Strain Strategy for Efficient Alkaline Hydrogen Evolution

ABSTRACT Nickel‐based materials are highly remarkable as promising transition metal catalysts for the electrochemical hydrogen evolution reaction (HER) in alkaline electrolytes. However, their electrochemical performance is limited by an unfavorable d‐band energy ( E d ) level. Herein, we showcase an effective lattice‐strain strategy to modulate the E d of Ni sites for achieving optimal alkaline HER kinetics. A specially designed mold spore carbon (MSC)‐confined Ni/NiO catalyst with lattice compressive strain (denoted as s‐Ni/NiO@MSC) is synthesized through a facile salt‐assisted pyrolysis method. Based on X‐ray absorption fine structure (XAFS) analysis and density functional theory (DFT) calculations, the intrinsic heteroatoms (N, P, and S) in MSC serve as anchoring sites to enhance the electronic interaction between Ni and the carbon matrix, thereby facilitating water adsorption. Furthermore, the lattice compressive strain at unsaturated Ni sites promotes electron redistribution and shortening Ni‐Ni bonds, which further regulates the Ni E d to balance the adsorption/desorption capacities of water and key intermediates (H* and OH*). As a result, s‐Ni/NiO@MSC displays enhanced alkaline HER performance, requiring a low potential of 81 mV to achieve 10 mA cm − 2 while maintaining stability for over 100 h at 100 mA cm −2 . This study not only provides effective insights for the construction of carbon‐confined nickel catalysts but also offers an important reference for optimizing the alkaline HER kinetics through the rational regulation of the d‐band center of transition metals by a lattice strain strategy.