Atomically dispersed chromium coordinated with hydroxyl clusters enabling efficient hydrogen oxidation on ruthenium.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 36202856.
- Also identified by DOI 10.1038/s41467-022-33625-x and PMC identifier 9537559.
- 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
Overcoming the sluggish kinetics of alkaline hydrogen oxidation reaction (HOR) is challenging but is of critical importance for practical anion exchange membrane fuel cells. Herein, abundant and efficient interfacial active sites are created on ruthenium (Ru) nanoparticles by anchoring atomically isolated chromium coordinated with hydroxyl clusters (Cr1(OH)x) for accelerated alkaline HOR. This catalyst system delivers 50-fold enhanced HOR activity with excellent durability and CO anti-poisoning ability via switching the active sites from Ru surface to Cr1(OH)x-Ru interface. Fundamentally different from the conventional mechanism merely focusing on surface metal sites, the isolated Cr1(OH)x could provide unique oxygen species for accelerating hydrogen or CO spillover from Ru to Cr1(OH)x. Furthermore, the original oxygen species from Cr1(OH)x are confirmed to participate in hydrogen oxidation and H2O formation. The incorporation of such atomically isolated metal hydroxide clusters in heterostructured catalysts opens up new opportunities for rationally designing advanced electrocatalysts for HOR and other complex electrochemical reactions. This work also highlights the importance of size effect of co-catalysts, which should also be paid substantial attention to in the catalysis field.