Heterostructure Induced S p‐Band Center Shift for Activating 1T‐MoS₂ Basal Plane towards Hydrogen Evolution Reaction

Abstract Despite the benefits of metallic conductivity and highly active edge Mo sites of 1T phase molybdenum disulfide (1T‐MoS₂) as an electrocatalyst, its overall catalytic efficiency for hydrogen evolution reaction (HER) is still limited by the less active S sites on the basal plane with a considerable positive ΔG_H*. As a result, activating the basal plane S atoms is a viable solution for increasing catalytic activity. In this work, we modulated the electronic structure of 1T‐MoS₂ by constructing a heterostructure with CoS₂ nanoparticles deposited on the 1T‐MoS₂ basal plane. This heterostructure demonstrated excellent HER activity as well as robust stability. Theoretical calculations indicate that the bridge S atoms connecting 1T‐MoS₂ and CoS₂ have an up‐shifted p‐band center relative to the S atoms on the basal plane, so the ΔG_H* of the bridge S atoms is optimized to thermal neutrality and the 1T‐MoS₂ basal plane is activated with enhanced hydrogen evolution activity. This work provides a novel strategy for activating the basal plane S atoms of 1T‐MoS₂.