Wrinkling Facilitated Hydrogen Evolution Reaction on Non-Noble Transition-Metal Single Atoms Anchored at Vacancy-Defected MoS2 Monolayer

Activating and enhancing the electrocatalytic performance of the monolayer MoS2 basal plane is crucial for reducing the cost of the hydrogen production. By screening fourth-period transition metal single atoms and combining extensive first-principles calculations, we find that a non-noble Zn single atom adsorbed on monolayer MoS2 with a single sulfur-vacancy defect (denoted as V1) exhibits promising electrocatalytic activity. Compressive strain induces wrinkling deformation in MoS2, which effectively tunes the hydrogen adsorption Gibbs free energy ΔGH*. Notably, the ΔGH* of MoS2–V1–Zn reaches 0.005 eV under 10.0% compressive strain, approaching the ideal value of 0 eV. Electronic structure analysis reveals that both transition metal single atoms and wrinkling deformation modulate the band structures, partial charge densities and projected density of states of the active sites, thereby optimizing the adsorption strength of hydrogen. Furthermore, a SISSO-derived descriptor based on the physicochemical characteristics of the catalyst is identified, which correlates with hydrogen adsorption energy and offers an efficient approach for predicting the ΔGH*. This work proposes an attractive strategy for designing non-noble single-atom catalysts on MoS2 basal plane for the hydrogen evolution reaction through utilizing the defect and strain engineering.