Non-Metal Doped VTe2 Monolayer: Theoretical Insights into the Enhanced Mechanism for Hydrogen Evolution Reaction

Abstract

Two-dimensional transition metal dichalcogenides (TMDCs), such as vanadium ditelluride (VTe2), have emerged as promising catalysts for the hydrogen evolution reaction (HER) due to their unique layered structures and remarkable electronic properties. However, the catalytic performance of pristine VTe2 remains inferior to that of noble metals. In this study, density functional theory (DFT) calculations were employed to systematically investigate the influence of fourteen different non-metal dopants on the HER activity of VTe2. Our results disclose that N-VTe2, P-VTe2 and As-VTe2 possess exceptional catalytic properties for the HER with the Gibbs free energy of hydrogen adsorption (GH*) values of 0.031, −0.032 and 0.024 eV, respectively. Furthermore, analyses of the geometric and electronic structures reveal that non-metal doping induces localized geometric distortions and charge redistribution, thereby altering the electronic environment of active sites and enhancing catalytic performance. More importantly, a composite descriptor , integrating the bond length between doped non-metal atoms and neighboring V atoms (LNM-M) and the pz band center (pz) of the doped atoms, demonstrates a strong correlation with GH* and may serve as an effective predictor of HER activity. These findings shed light on non-metal doping as an effective strategy for developing efficient, non-noble metal HER catalysts based on TMDCs.