Restructuring electronic structure via W doped 1T MoS2 for enhancing hydrogen evolution reaction.

[Display omitted] • 1. W doped 1T MoS 2 has been synthesized via hydrothermal. • 2. W doped into 1T MoS 2 causes electrons redistribution on the surface. • 3. W-1T MoS 2 -15 demonstrated the excellent HER activity and stability. • 4. DFT calculations demonstrated that W doped 1T MoS 2 could reduce the ΔG H*. The intrinsic electronic structure on the surface of 1T MoS 2 makes the non-optimal bonding strength with hydrogen atoms, which is the key factor that the catalytic performance cannot be improved. However, modifying surface electronic structure by doped exotic atom is an effective approach to optimal the bonding strength between hydrogen atoms and 1T MoS 2. Herein, this work reports W doped 1T MoS 2 with different concentrations by hydrothermal method. The results indicate that W-1T MoS 2 -15 exhibits excellent catalytic activity for hydrogen evolution reaction (HER), the catalytic activity is better than that of 2H MoS 2 and pristine 1T MoS 2 , the lowest overpotential and tafel slope in acid electrolyte is 292 mV and 55.7 mV dec−1, respectively. Theoretical calculation results show that W-1T MoS 2 -2/9 has relatively much lower barrier than pristine 1T MoS 2 both in Volmer reaction and Heyrovsky reaction. Therefore, W-1T MoS 2 -2/9 has a faster reaction kinetics for HER. In addition, introducing W atoms can trigger spontaneous electrons redistribution on the basal plane, optimize energy level, and reduce the Gibbs free energy. This study confirmed that doping of atom with similar physical and chemical properties can optimize electronic structure of 1T MoS 2 on the basal plane, and effectively improve its electrocatalytic activity. [ABSTRACT FROM AUTHOR]