Electronic-reconstruction-enhanced hydrogen evolution catalysis in oxide polymorphs.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 31316069.
- Also identified by DOI 10.1038/s41467-019-11124-w and PMC identifier 6637208.
- 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
Transition metal oxides exhibit strong structure-property correlations, which has been extensively investigated and utilized for achieving efficient oxygen electrocatalysts. However, high-performance oxide-based electrocatalysts for hydrogen evolution are quite limited, and the mechanism still remains elusive. Here we demonstrate the strong correlations between the electronic structure and hydrogen electrocatalytic activity within a single oxide system Ti<sub>2</sub>O<sub>3</sub>. Taking advantage of the epitaxial stabilization, the polymorphism of Ti<sub>2</sub>O<sub>3</sub> is extended by stabilizing bulk-absent polymorphs in the film-form. Electronic reconstructions are realized in the bulk-absent Ti<sub>2</sub>O<sub>3</sub> polymorphs, which are further correlated to their electrocatalytic activity. We identify that smaller charge-transfer energy leads to a substantial enhancement in the electrocatalytic efficiency with stronger hybridization of Ti 3d and O 2p orbitals. Our study highlights the importance of the electronic structures on the hydrogen evolution activity of oxide electrocatalysts, and also provides a strategy to achieve efficient oxide-based hydrogen electrocatalysts by epitaxial stabilization of bulk-absent polymorphs.