Beyond domain alignment: Revealing the effect of intrinsic magnetic order on electrochemical water splitting

• DOI: 10.48550/arxiv.2308.16654
• Publication Date: 2023-01-01
• Authors: Emma van der Minne; Lucas Korol; Lidewij M. A. Kra...; Michael Verhage; Carlos M. M. Rosário; Thijs J. Roskamp; Raymond J. Spiteri; Chiara Biz; Mauro Fianchini; Guus Rijnders; Kees Flipse; José Gracia; Guido Mul; H. Hilgenkamp; Robert J. Green; Gertjan Koster; Christoph Baeumer
• Keywords: Condensed Matter - Materials Science; Materials Science (cond-mat.mtrl-sci); FOS: Physical sciences; 7. Clean energy

To reach a long term viable green hydrogen economy, rational design of active oxygen evolution reaction (OER) catalysts is critical. An important hurdle in this originates from the fact that reactants are singlet molecules, whereas molecule has triplet ground state with parallel spin alignment, implying magnetic order catalyst essential. Accordingly, multiple experimentalists reported positive effect external fields on OER activity ferromagnetic catalysts. However, it remains challenge to investigate influence intrinsic catalytic activity. Here, we tuned epitaxial La$_{0.67}$Sr$_{0.33}$MnO$_{3}$ thin film model ferro- paramagnetic by changing temperature in-situ during water electrolysis. Using strategy, show ordering below Curie enhances Moreover, slight current density enhancement upon application an field and find dependence direction correlates anisotropy film. Our work thus suggests both films domain alignment increase their We observe no long-range at surface, connected bulk catalyst. Combining effects found existing literature, propose unifying picture for spin-polarized oxide