Multi-site electrocatalysts for hydrogen production under neutral conditions

Abstract

Electrochemical water splitting offers a sustainable pathway for hydrogen production, yet realizing high-efficiency operation at neutral pH remains a formidable challenge due to the sluggish interfacial kinetics, limited ionic conductivity, and complex proton transfer behavior. Recently, the emergence of multi-site electrocatalysts has provided a powerful strategy to decouple and optimize each elementary step of the neutral hydrogen evolution reaction (HER). This review presents a timely and in-depth analysis of the reaction mechanisms, electrolyte effects, and interfacial micro-environments that define the HER under neutral conditions. We highlight the recent progress in the performance metrics, design, synthesis, and structural engineering of multi-site catalytic systems, with an emphasis on their role in facilitating water dissociation and hydrogen evolution, along with critical discussions on advanced characterization techniques. Finally, we examine the prospects of translating laboratory-scale discoveries to practical neutral-pH water electrolysis systems. This review aims to offer a foundational understanding and forward-looking perspectives for developing next-generation electrocatalysts tailored to neutral water splitting.