Activating and optimizing the In-Plane interface of 1 T/2H MoS2 for efficient hydrogen evolution reaction

Implanting the octahedral phase (1 T) into the hexagonal phase (2H) of the molybdenum disulfide (MoS2) matrix is considered one of the effective methods to enhance hydrogen evolution reaction (HER) performances of MoS2. In this paper, hybrid 1 T/2H MoS2 nanosheets array was successfully grown on conductive carbon cloth (1 T/2H MoS2/CC) via facile hydrothermal method and the 1 T phase content in 1 T/2H MoS2 is regulated to gradually increase from 0 % to 80 %. 1 T/2H MoS2/CC with 75 % 1 T phase content exhibits optimal HER performances. The DFT calculation results show that S atoms in 1 T/2H MoS2 interface exhibit the lowest hydrogen adsorption Gibbs free energies (ΔGH*) compared with other sites. The improvement of HER performances are primarily attributed to activating the in-plane interface regions of the hybrid 1 T/2H MoS2 nanosheets. Furthermore, the relationship between 1 T MoS2 content in 1 T/2H MoS2 and catalytic activity was simulated by a mathematical model, which shows that the catalytic activity presents a trend of increasing and then decreasing with the increase of 1 T phase content.