High-spin Co<sup>3+</sup> in cobalt oxyhydroxide for efficient water oxidation.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 38360821.
- Also identified by DOI 10.1038/s41467-024-45702-4 and PMC identifier 10869355.
- 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
Cobalt oxyhydroxide (CoOOH) is a promising catalytic material for oxygen evolution reaction (OER). In the traditional CoOOH structure, Co<sup>3+</sup> exhibits a low-spin state configuration ([Formula: see text]), with electron transfer occurring in face-to-face [Formula: see text] orbitals. In this work, we report the successful synthesis of high-spin state Co<sup>3+</sup> CoOOH structure, by introducing coordinatively unsaturated Co atoms. As compared to the low-spin state CoOOH, electron transfer in the high-spin state CoOOH occurs in apex-to-apex [Formula: see text] orbitals, which exhibits faster electron transfer ability. As a result, the high-spin state CoOOH performs superior OER activity with an overpotential of 226 mV at 10 mA cm<sup>-2</sup>, which is 148 mV lower than that of the low-spin state CoOOH. This work emphasizes the effect of the spin state of Co<sup>3+</sup> on OER activity of CoOOH based electrocatalysts for water splitting, and thus provides a new strategy for designing highly efficient electrocatalysts.