Sulfur vacancies and group VB metal atoms doping to synergistically optimize hydrogen evolution of MoS2 nanosheets

Abstract

Molybdenum disulfide (MoS2) based materials exhibit promising potential for hydrogen evolution reaction (HER) performance and stability. Nevertheless, they face key challenges in electrochemical water splitting application as a result of their inert basal planes and limited active sites. On this basis, we attempt to systematically explore the effects of doping group VB metals and introducing sulfur (S) vacancies on improving the inherent conductivity and active sites of MoS2. The experimental consequences show that the catalytic activity of MoS2 doped with group VB metal elements and S-vacancies is significantly different from that of the pure MoS2 samples. In particular, the Nb-doped MoS2 catalyst has better performance than the pure MoS2. Additionally, density functional theory computations further confirm that the synergistic effects of group VB elements and S vacancies enhance the adsorption capacity of hydrogen atoms, resulting in boosting HER performance of the catalysts. The doping of group VB elements can optimize and improve the property of MoS2, which provides a new idea for designing efficient electrocatalysts doped with subgroup elements.