Molybdenum Disulfide Modified by Laser Irradiation for Catalyzing Hydrogen Evolution

As a low-cost and promising electrocatalyst for hydrogen evolution reaction (HER), molybdenum disulfide (MoS2) possesses both an inert basal plane and catalytically active edges. As a result, considerable efforts have been made to activate the MoS2 basal plane for improving the HER activity. Herein, we first employed laser ablation in liquid to create plentiful sulfur (S)-vacancies in the basal plane of 2H-MoS2 nanosheets under ambient conditions. The experimental measurements and theoretical calculations prove that S vacancies in the basal plane can serve as the additional active sites and optimize the free energy change for hydrogen adsorption (ΔGH*) at the same time. As a result, in comparison with pristine MoS2 (P-MoS2), laser treated MoS2 (L-MoS2) realizes a significant improvement in the HER activity. Our work represents a facile method to enhance the catalytic performance of 2H-MoS2 nanosheets and may help to guide the synthesis of other efficient two-dimensional metal chalcogenide catalysts.