In:
Energy & Environmental Science, Royal Society of Chemistry (RSC), Vol. 15, No. 1 ( 2022), p. 206-214
Kurzfassung:
The oxygen evolution reaction (OER) is the bottleneck reaction of water splitting, which can be used to generate green hydrogen from renewable electricity. Cobalt iron oxyhydroxides (CoFeO x H y ) are among the most active OER catalysts in alkaline medium. However, the active sites of these catalysts remain unclear. Here we use operando ultraviolet-visible (UV-Vis), X-ray absorption, and Raman spectroscopy to reveal oxidations of both Fe and Co ions in CoFeO x H y during the OER. By analyzing samples with different Fe contents and thickness, we find that the concentration of Fe 4+ species at the surface, but not the concentration of Co 4+ in the bulk, scales with the catalytic activity. These results indicate an Fe 4+ -containing active site in CoFeO x H y .
Materialart:
Online-Ressource
ISSN:
1754-5692
,
1754-5706
Sprache:
Englisch
Verlag:
Royal Society of Chemistry (RSC)
Publikationsdatum:
2022
ZDB Id:
2439879-2
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