Advances in Design Strategy and Mechanism Insights for Alkaline Hydrogen Evolution Reaction: Multilevel Site Engineering and Structure–Activity Relationship

Electrolytic water splitting is a clean, carbon‐free method for producing green hydrogen and has drawn significant attention. However, transition metal‐based electrocatalysts show much lower hydrogen evolution reaction (HER) activity in alkaline than in acidic conditions due to unclear structure–activity relationships. This article systematically examines the mechanism of alkaline HER and proposes practical design strategies for efficient electrocatalysts. In particular, dual‐site electrocatalysts enhance performance by enabling synergistic H ₂ O dissociation and *H activation. These theoretical insights and strategic design principles offer practical guidance for the rational development of efficient alkaline HER electrocatalysts.