title: Effect of Doping on Hydrogen Evolution Reaction of Vanadium Disulfide Monolayer.
abstract: As cheap and abundant materials, transitional metal dichalcogenide monolayers have attracted increasing interests for their application as catalysts in hydrogen production. In this work, the hydrogen evolution reduction of doped vanadium disulfide monolayers is investigated based on first-principles calculations. We find that the doping elements and concentration affect strongly the catalytic ability of the monolayer. We show that Ti-doping can efficiently reduce the Gibbs free energy of hydrogen adsorption in a wide range of hydrogen coverage. The catalytic ability of the monolayer at high hydrogen coverage can be improved by low Ti-density doping, while that at low hydrogen coverage is enhanced by moderate Ti-density doping. We further show that it is much easier to substitute the Ti atom to the V atom in the vanadium disulfide (VS2) monolayer than other transitional metal atoms considered here due to its lowest and negative formation energy. It is expected that the Ti-doped VS2 monolayer may be applicable in water electrolysis with improved efficiency.
authors.affiliation: Institute of Applied Physics and Materials Engineering, Faculty of Science and Technology, University of Macau, Macao, SAR, People's Republic of China.|Department of Electromechanical Engineering, Faculty of Science and Technology, University of Macau, Macao, SAR, People's Republic of China.|College of Physics and Communication Electronics, Jiangxi Normal University, Nanchang, 330022, People's Republic of China.
authors.forename: Yuanju
authors.initials: Y
authors.lastname: Qu
authors.affiliation: Institute of Applied Physics and Materials Engineering, Faculty of Science and Technology, University of Macau, Macao, SAR, People's Republic of China. huipan@umac.mo.
authors.forename: Hui
authors.initials: H
authors.lastname: Pan
authors.affiliation: Institute of Applied Physics and Materials Engineering, Faculty of Science and Technology, University of Macau, Macao, SAR, People's Republic of China.|Department of Electromechanical Engineering, Faculty of Science and Technology, University of Macau, Macao, SAR, People's Republic of China.
authors.forename: Chi Tat
authors.initials: CT
authors.lastname: Kwok
authors.affiliation: Institute of Applied Physics and Materials Engineering, Faculty of Science and Technology, University of Macau, Macao, SAR, People's Republic of China.|College of Physics and Communication Electronics, Jiangxi Normal University, Nanchang, 330022, People's Republic of China.
authors.forename: Zisheng
authors.initials: Z
authors.lastname: Wang
keywords: Doping; First-principles calculation; Hydrogen evolution reduction; Hydrogen production; VS2 monolayers