Triggering the Inert Basal Planes of Curved MoS ₂ by Rational Strain Engineering of Single-Atom Pt toward Enhanced Hydrogen Evolution Reaction

Strain engineering has been considered as a promising strategy for constructing strained two-dimensional (2D) materials to trigger inert basal planes and anchor single-atom active sites but continues to be a challenge. Herein, we present a curved molybdenum disulfide nanosheet with in-plane strain and anchored Pt single atoms (sMoS₂-Pt). The strain engineering of curved MoS₂ induces the formation of sulfur vacancies, while the introduction of Pt single atoms promotes the phase transformation of sMoS₂ from semiconducting 2H to metallic 1T. According to theoretical calculations, the synergistic effect of the Pt single atoms and bending strain achieves a lower hydrogen adsorption energy (-0.04 eV), thereby enhancing the hydrogen evolution reaction (HER) performance. The sMoS₂ with activated inert basal planes exhibits a lower overpotential of 72 and 102 mV across both acidic and alkaline electrolytes at 10 mA cm^-2. When employed as a cathode in a proton exchange membrane water electrolysis cell (PEMWE), after continuous operation for 85 h at a constant voltage of 1.79 V, approximately 80.8% of the current density was still retained, demonstrating good stability. This work offers a strain engineering strategy for designing MoS₂ and other 2D materials-based electrocatalysts and elucidates the HER mechanism of strained MoS₂.