Advancing Multiscale-Coupled Heterointerface Catalysts for Enhanced Water Electrolysis

Abstract

Green electricity powered water electrolysis stands out as a promising approach for hydrogen production, which is regarded as an ideal energy carrier due to its high energy density and clean combustion. However, its large-scale application is constrained by the high cost, stemming partially from the reliance on noble-metal-based catalysts to enhance the sluggish kinetics of hydrogen and oxygen evolution reactions. To address this challenge, multiscale-coupled heterointerface catalysts (MCHCs), which integrate single atoms, clusters, and nanoparticles into one independent system, have emerged as a potential alternative. They are composed of different active components at multiple scales to achieve strong synergistic effects, where single atoms provide highly active sites with unsaturated coordination environments, clusters enable tunable electronic properties to optimize intermediate binding, and nanoparticles contribute to conductive compensation and robust architecture. Through coupling engineering, these formed heterointerfaces can regulate electronic structures and geometric configurations to break the linear scaling relationship (LSR), simultaneously facilitating H₂O activation and intermediate removal. Accordingly, such synergy enables the MCHCs to overcome thermodynamic and kinetic barriers in water electrolysis, significantly boosting the catalytic performance and durability.