Mechanical, electronic and catalytic properties of 2H-1T' MoS2 heterointerfaces.

Using first-principles calculations, we comprehensively explored the influence of 2H-1T' heterointerfaces in molybdenum disulfide (MoS2) on the mechanical, electronic and catalytic properties of MoS2. The S-orientated interfaces, including interfaces with interstitial S or S vacancies, were adopted as samples. All the heterostructures show a smaller yield stress than 2H and 1T' MoS2, and fractures always occur at the interface. The heterostructures are either metallic or half-metallic. Some of the heterointerfaces show great catalytic ability for the hydrogen evolution reaction (HER). In particular, the Gibbs free energy of H adsorption is as low as -0.028 eV for the S-LU-sint structure. Moreover, a small strain of 4% can improve the HER catalytic activity for several heterostructures. Our results show that 2H-1T' MoS2 heterointerfaces are potential catalysts for the HER.