Transition-metal-free boron doped SbN monolayer for N2 adsorption and reduction to NH3: A first-principles study

Dachang Chen; Zhiwen Chen; Lixin Chen; Yi Li; Song Xiao; Beibei Xiao

doi:10.1016/j.jcis.2021.09.026

Transition-metal-free boron doped SbN monolayer for N₂ adsorption and reduction to NH₃: A first-principles study

J Colloid Interface Sci. 2022 Feb;607(Pt 2):1551-1561. doi: 10.1016/j.jcis.2021.09.026. Epub 2021 Sep 26.

Authors

Dachang Chen¹, Zhiwen Chen², Lixin Chen², Yi Li³, Song Xiao³, Beibei Xiao⁴

Affiliations

¹ School of Electrical and Electronic Engineering, Wuhan Polytechnic University, Wuhan 430023, China. Electronic address: dcchen.wuhan@outlook.com.
² Key Laboratory of Automobile Materials, Ministry of Education, School of Materials Science and Engineering, Jilin University, Changchun 130022, China; Department of Materials Science and Engineering, University of Toronto, 184 College Street, Suite 140, Toronto, ON M5S 3E4, Canada.
³ School of Electrical Engineering and Automation, Wuhan University, Wuhan 430072, China.
⁴ School of Energy and Power Engineering, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu 212003, China.

PMID: 34587530
DOI: 10.1016/j.jcis.2021.09.026

Abstract

Electrochemical nitrogen reduction reaction (NRR) in ambient condition is an efficient and sustainable method to synthesize NH₃. In this work, first-principles study was used to discuss the NRR process on B atom doped SbN monolayer. The adsorption of N₂ on B-Sb₁₇N₁₈ and B-S₁₈N₁₇ was calculated including the adsorption energy, adsorption distance, and the charge density difference (CDD). Five different reaction pathways of NRR were taken into consideration and the stability of B-SbN was investigated. The results show that, because the energy of unoccupied orbital in sp³ hybridization of B atom is much lower than that in 2p_z orbitals, the adsorption of N₂ on B-Sb₁₈N₁₇ shows much larger adsorption energy (-1.01 eV with end-on pattern) compared to that of the adsorption on B-Sb₁₇N₁₈. For five different pathways, the 1, 2, and 4 pathways have a smaller limiting potential of about 0.52 V and the limiting step is: *N₂ + H⁺ + e^- → *NNH. The 3 and 5 pathways have a larger limiting potential of 0.57 V with hydrogenation step: *NHNH₂ + H⁺ + e^- → *NH₂NH₂. The B-Sb₁₈N₁₇ is structurally and thermally stable even at 500 K. Our theoretical prediction indicates that B atom substitutionally doped SbN monolayer can be a kind of high-performance metal-free NRR catalyst for NH₃ synthetization, and the work provides attempts for designing and exploring 2D metal-free NRR catalysts.

Keywords: B doping; First-principles study; Nitrogen reduction reaction (NRR); SbN monolayer; Transition-metal-free catalyst.