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Influence of iron doping on tetravalent nickel content in catalytic oxygen evolving films.

ABSTRACT: Iron doping of nickel oxide films results in enhanced activity for promoting the oxygen evolution reaction (OER). Whereas this enhanced activity has been ascribed to a unique iron site within the nickel oxide matrix, we show here that Fe doping influences the Ni valency. The percent of Fe3+ doping promotes the formation of formal Ni4+, which in turn directly correlates with an enhanced activity of the catalyst in promoting OER. The role of Fe3+ is consistent with its behavior as a superior Lewis acid.

SUBMITTER: Li N

PROVIDER: S-EPMC5321006 | biostudies-other | 2017 Feb

REPOSITORIES: biostudies-other

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Influence of iron doping on tetravalent nickel content in catalytic oxygen evolving films.

Li Nancy N Bediako D Kwabena DK Hadt Ryan G RG Hayes Dugan D Kempa Thomas J TJ von Cube Felix F Bell David C DC Chen Lin X LX Nocera Daniel G DG

Proceedings of the National Academy of Sciences of the United States of America 20170130 7

Iron doping of nickel oxide films results in enhanced activity for promoting the oxygen evolution reaction (OER). Whereas this enhanced activity has been ascribed to a unique iron site within the nickel oxide matrix, we show here that Fe doping influences the Ni valency. The percent of Fe3+ doping promotes the formation of formal Ni4+, which in turn directly correlates with an enhanced activity of the catalyst in promoting OER. The role of Fe3+ is consistent with ...[more]

PMID: 28137835

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