Defects Engineered Monolayer MoS₂ for Improved\nHydrogen Evolution Reaction

Abstract

MoS₂ is a promising and\nlow-cost material for electrochemical hydrogen production due to its\nhigh activity and stability during the reaction. However, the efficiency\nof hydrogen production is limited by the amount of active sites, for\nexample, edges, in MoS₂. Here, we demonstrate that oxygen\nplasma exposure and hydrogen treatment on pristine monolayer MoS₂ could introduce more active sites via the formation of defects\nwithin the monolayer, leading to a high density of exposed edges and\na significant improvement of the hydrogen evolution activity. These\nas-fabricated defects are characterized at the scale from macroscopic\ncontinuum to discrete atoms. Our work represents a facile method to\nincrease the hydrogen production in electrochemical reaction of MoS₂ via defect engineering, and helps to understand the catalytic\nproperties of MoS₂.