Tuning the surface reducibility of perovskite supports for optimized Pt-based alkaline hydrogen evolution reaction electrocatalysts

Understanding of how interactions between the support materials and Pt electrocatalysts affect electrocatalytic activity behavior is crucial for designing efficient hydrogen evolution reaction (HER) electrocatalysts in alkaline media. In this study, we systematically investigate Pt nanoparticles supported on La-based perovskites with different B-site metals (LaMO₃, M = Ni, Co, and Fe) to elucidate the correlation between the support properties and the electrocatalytic activity of Pt. Modulating the B-site metal in LaMO₃ governs the surface reducibility of the support, which regulates the oxygen vacancy concentration of perovskite supports and the d-band center of the supported Pt. This, in turn, significantly affects H₂O dissociation kinetics and hydrogen adsorption behavior. Among the series, Pt supported on the LaNiO₃ exhibited the highest alkaline HER activity, characterized by a near-zero water dissociation barrier (0.01 eV) and the most optimally tuned hydrogen adsorption energy (−0.08 eV). These findings demonstrate that tailoring the electronic structure and surface properties of perovskite supports is an effective strategy for optimizing Pt-support interactions and advancing the design of high-performance Pt-based electrocatalysts for alkaline HER electrocatalysts.