Elucidating catalytic sites governing the performance toward the hydrogen evolution reaction in ternary nitride electrocatalysts

Sun, Y., Sviridova, E., Kamp, M., Zhang, J., Kienle, L., Moran, D. A.J. , Guselnikova, O. and Ganin, A. Y. (2023) Elucidating catalytic sites governing the performance toward the hydrogen evolution reaction in ternary nitride electrocatalysts. ACS Applied Energy Materials, 6(3), pp. 1265-1273. (doi: 10.1021/acsaem.2c02941)

Abstract

Proton exchange membrane electrolyzers are considered the most advanced devices for producing green hydrogen by water electrolysis. Their development requires catalytic materials that are stable under acidic conditions and drive the hydrogen evolution reaction (HER) forward efficiently which makes research into the identification of the catalytic sites important. We report that free-standing Co2Mo3N and Ni2Mo3N achieve overpotentials of 149 ± 8 and 158 ± 10 mV (in 0.5 M H2SO4) at a benchmark current density of 10 mA cm–2. Both nitrides remained stable and consistently deliver current densities >500 mA cm–2 at a potential as low as 308 ± 22 mV when they were immobilized on nickel foam. Replacing Ni for Fe in Ni2Mo3N leads to FexNi2–xMo3N (0.5 ≤ x ≤ 1.25) that show a decrease in catalytic activity as the value of x increases which confirms that Ni (rather than Mo and N) sites are catalytically active. The X-ray photoelectron spectroscopy data additionally suggests that preserving the low oxidation states of transition metals in the nitrides is important for achieving good catalytic performance toward the HER in acidic electrolytes.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Zhang, Jingyi and Ganin, Dr Alexey and Sviridova, Elizaveta and Moran, Professor David and Sun, Youyi
• Authors: Sun, Y., Sviridova, E., Kamp, M., Zhang, J., Kienle, L., Moran, D. A.J., Guselnikova, O., and Ganin, A. Y.
• College/School: College of Science and Engineering > School of Chemistry; College of Science and Engineering > School of Engineering > Electronics and Nanoscale Engineering
• Journal Name: ACS Applied Energy Materials
• Publisher: American Chemical Society
• ISSN: 2574-0962
• ISSN (Online): 2574-0962
• Published Online: 18 January 2023
• Copyright Holders: Copyright © 2023 The Authors
• First Published: First published in ACS Applied Energy Materials 6(3): 1265-1273
• Publisher Policy: Reproduced under a Creative Commons License