Spin-related symmetry breaking induced by half-disordered hybridization in Bi<sub>x</sub>Er<sub>2-x</sub>Ru<sub>2</sub>O<sub>7</sub> pyrochlores for acidic oxygen evolution.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 35840581.
- Also identified by DOI 10.1038/s41467-022-31874-4 and PMC identifier 9287408.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
While acidic oxygen evolution reaction plays a critical role in electrochemical energy conversion devices, the sluggish reaction kinetics and poor stability in acidic electrolyte challenges materials development. Unlike traditional nano-structuring approaches, this work focuses on the structural symmetry breaking to rearrange spin electron occupation and optimize spin-dependent orbital interaction to alter charge transfer between catalysts and reactants. Herein, we propose an atomic half-disordering strategy in multistage-hybridized Bi<sub>x</sub>Er<sub>2-x</sub>Ru<sub>2</sub>O<sub>7</sub> pyrochlores to reconfigure orbital degeneracy and spin-related electron occupation. This strategy involves controlling the bonding interaction of Bi-6s lone pair electrons, in which partial atom rearrangement makes the active sites transform into asymmetric high-spin states from symmetric low-spin states. As a result, the half-disordered Bi<sub>x</sub>Er<sub>2-x</sub>Ru<sub>2</sub>O<sub>7</sub> pyrochlores demonstrate an overpotential of ~0.18 V at 10 mA cm<sup>-2</sup> accompanied with excellent stability of 100 h in acidic electrolyte. Our findings not only provide a strategy for designing atom-disorder-related catalysts, but also provides a deeper understanding of the spin-related acidic oxygen evolution reaction kinetics.