Wrinkles in 2D TMD heterostructures: unlocking enhanced hydrogen evolution reaction catalysis

Abstract

Two-dimensional (2D) transition metal dichalcogenides (TMDs) have demonstrated high catalytic activity for the hydrogen evolution reaction (HER). However, these materials usually form with wrinkles instead of being perfectly planar, which induce internal strain, alter the electronic properties and consequently influence the catalytic performance. The impact of wrinkles on the HER catalytic activity of 2D TMDs is essential to understanding the structure–property relationship under real conditions and requires specific investigations. By employing first-principles calculations and following the Euler–Bernoulli beam theory, we systematically explore the effect of intrinsic wrinkles of the MoSSe/WSSe lateral heterostructure on their electronic structure and catalytic performance for the HER. We demonstrate that the polarity of the MoSSe/WSSe heterostructure is reduced with a wrinkled configuration. We reveal the high HER activity of the wrinkled MoSSe/WSSe heterostructure by showing a low overpotential of −0.18 V, which can be favorably tuned by applying external strain because of its high strength and good elasticity. The strain-dependent HER performance is rationalized by the linear correlation between the applied strain and the reaction energy. Our investigation reveals the role of intrinsic wrinkles in determining the mechanical and electronic properties and catalytic performance of 2D TMDs, and sheds new light on the rational design of TMD heterostructures for effective HER by taking advantage of wrinkled morphologies.