Titanium-doped MoS2monolayer as highly efficient catalyst for hydrogen evolution reaction

Abstract

The effects of Ti dopants on the catalytic activities of the hydrogen evolution reaction (HER) in monolayer MoS2 basal plane were investigated using density functional theory. Our study shows that Ti dopants that substituted Mo atoms in MoS2 have small formation energy, and the complex dopant structures involving multiple Ti sites are energetically more stable than the isolated ones. Doping Ti atoms greatly improves the catalytic performances of MoS2 with a near-ideal hydrogen-adsorption Gibbs free energy. Projected density of states analysis revealed that the mechanism for the improvement of catalytic activity is due to formation of the density of states near the Fermi energy level upon increasing dopant concentrations. It can be expected from the current results that excellent catalytic performance can be obtained by atomic composition modifications, such as Ti doping in the HER reaction.