Theoretical Screening of Transition Metal-Embedded Ti2N for High-Efficiency Hydrogen Evolution Reaction

Lingyan Kong; Xiongyi Liang; Maohuai Wang; Chi-Man Lawrence Wu

doi:10.1021/acssuschemeng.1c07741

Author(s)

Related Research Unit(s)

Department of Materials Science and Engineering

Detail(s)

Original language	English
Pages (from-to)	4152–4160
Journal / Publication	ACS Sustainable Chemistry & Engineering
Volume	10
Issue number	13
Online published	18 Mar 2022
Publication status	Published - 4 Apr 2022

Link(s)

DOI	DOI https://doi.org/10.1021/acssuschemeng.1c07741 Final Published version
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Attachment(s)	Documents 97220178.pdf Post-print, 1.72 MB, PDF Publisher's Copyright Statement COPYRIGHT TERMS OF DEPOSITED POSTPRINT FILE: This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Sustainable Chemistry & Engineering, copyright © 2022 American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acssuschemeng.1c07741.
Link to Scopus	https://www.scopus.com/record/display.uri?eid=2-s2.0-85127870150&origin=recordpage
Permanent Link	https://scholars.cityu.edu.hk/en/publications/publication(eeb395f7-b0f9-4e5a-8e67-66601020a028).html

Abstract

Transition metals (TMs) have been widely employed to realize various electrocatalytic applications of pristine materials. Herein, via density functional theory (DFT), the potential for the hydrogen evolution reaction (HER) of all single TMs embedded in Ti₂N was screened. Our results show that embedded single TMs can tune the hydrogen adsorption with a volcano-like tendency, and Mo-Ti₂N stands out with an optimal Gibbs free energy (ΔG_H) of −0.097 eV. This can be further improved with an optimal ΔG_H close to thermal neutrality by applying 1.2% tensile strain to Mo–Ti₂N, and the excellent exchange current density exceeds that of most conventional metal catalysts. The chemical nature of the Mo–H bond under strain was analyzed by revealing the changes in internal electronic structure and establishing the relationship with adsorption energy. The results reveal the bonding mechanisms to clearly show that a single TM atom embedded in Ti₂N such as Mo-Ti₂N is a feasible electrocatalyst for HER.