TY - JOUR
T1 - A Unified Theory for H2 Evolution on Mo-Based Electrocatalysts
AU - Bau, Jeremy
AU - Ahmad, Rafia
AU - Cavallo, Luigi
AU - Rueping, Magnus
N1 - KAUST Repository Item: Exported on 2022-10-07
Acknowledgements: This work was supported by the King Abdullah University of Science and Technology. L.C. and R.A. acknowledge Shaheen and the HPC Core Labs team at KAUST.
PY - 2022/10/3
Y1 - 2022/10/3
N2 - Mo-based catalysts constitute a significant portion of active non-noble H2 evolution reaction (HER) catalysts, but the role of Mo in conferring this activity remains debated. In this study, we utilize electrochemical, physical, functional, and computational approaches on a range of Mo-based catalysts to derive a unified explanation for Mo HER catalyst function. Across all catalysts studied, the formation of Mo3+ at cathodic potentials close to the thermodynamic HER onset drives activity, and activity between catalysts is therefore heavily determined by the ease of reduction from Mo4+ to Mo3+. As such, surface oxidation is detrimental to HER activity as it makes Mo3+ formation less facile. This theory provides a cohesive explanation for the origin of activity in Mo-based HER catalysts, emphasizing the specific role of Mo atoms in forming hydrides and carrying out the HER from Mo3+, with implications for future Mo catalyst design.
AB - Mo-based catalysts constitute a significant portion of active non-noble H2 evolution reaction (HER) catalysts, but the role of Mo in conferring this activity remains debated. In this study, we utilize electrochemical, physical, functional, and computational approaches on a range of Mo-based catalysts to derive a unified explanation for Mo HER catalyst function. Across all catalysts studied, the formation of Mo3+ at cathodic potentials close to the thermodynamic HER onset drives activity, and activity between catalysts is therefore heavily determined by the ease of reduction from Mo4+ to Mo3+. As such, surface oxidation is detrimental to HER activity as it makes Mo3+ formation less facile. This theory provides a cohesive explanation for the origin of activity in Mo-based HER catalysts, emphasizing the specific role of Mo atoms in forming hydrides and carrying out the HER from Mo3+, with implications for future Mo catalyst design.
UR - http://hdl.handle.net/10754/682264
UR - https://pubs.acs.org/doi/10.1021/acsenergylett.2c02053
U2 - 10.1021/acsenergylett.2c02053
DO - 10.1021/acsenergylett.2c02053
M3 - Article
SN - 2380-8195
SP - 3695
EP - 3702
JO - ACS Energy Letters
JF - ACS Energy Letters
ER -