Probing dynamic oxygen exchange for hydrogen production with operando neutron diffraction

Telford, Daniel M.; Martínez Martín, Alex; Guy, Matthew D.; Henry, Paul F.; Jones, Martin O.; Hu, Wenting; Metcalfe, Ian S.; Evans, John S. O.

Abstract

A chemical looping process exploiting the variable oxygen content of ABO3−δ perovskite materials can achieve super-equilibrium conversions of societally important reactions such as the water–gas shift reaction (CO + H2O ⇋ CO2 + H2). The approach relies on an evolving oxygen chemical potential gradient within a reactor bed. Here we show that the oxygen-sensitivity of operando neutron powder diffraction experiments can reveal how the reactor functions with high spatial- (≲1 cm) and time- (≲30 s) resolution. We show how this operando method enables rapid testing of new high-capacity bed materials without previous knowledge of their thermodynamic properties, and gives direct information on their long-term stability. We introduce how this memory reactor concept can also be applied to the steam methane reforming reaction (CH4 + H2O ⇋ CO + 3H2), the key preprocess to the water–gas shift reaction in H2 production.

Citation

Telford, D. M., Martínez Martín, A., Guy, M. D., Henry, P. F., Jones, M. O., Hu, W., Metcalfe, I. S., & Evans, J. S. O. (online). Probing dynamic oxygen exchange for hydrogen production with operando neutron diffraction. Nature Chemical Engineering, https://doi.org/10.1038/s44286-025-00231-9

• Journal Article Type: Article
• Acceptance Date: Apr 28, 2025
• Online Publication Date: Jun 4, 2025
• Deposit Date: Jun 6, 2025
• Publicly Available Date: Jun 6, 2025
• Journal: Nature Chemical Engineering
• Print ISSN: 2948-1198
• Electronic ISSN: 2948-1198
• Publisher: Nature Research
• Peer Reviewed: Peer Reviewed
• DOI: https://doi.org/10.1038/s44286-025-00231-9
• Public URL: https://durham-repository.worktribe.com/output/4091227