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Self-healing catalysis in water.

ABSTRACT: Principles for designing self-healing water-splitting catalysts are presented together with a formal kinetics model to account for the key chemical steps needed for self-healing. Self-healing may be realized if the catalysts are able to self-assemble at applied potentials less than that needed for catalyst turnover. Solution pH provides a convenient handle for controlling the potential of these two processes, as demonstrated for the cobalt phosphate (CoPi) water-splitting catalyst. For Co2+ ion that appears in solution due to leaching from the catalyst during turnover, a quantitative description for the kinetics of the redeposition of the ion during the self-healing process has been derived. The model reveals that OER activity of CoPi occurs with negligible film dissolution in neutral pH for typical cell geometries and buffer concentrations.

SUBMITTER: Costentin C

PROVIDER: S-EPMC5754779 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

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Self-healing catalysis in water.

Costentin Cyrille C Nocera Daniel G DG

Proceedings of the National Academy of Sciences of the United States of America 20170905 51

Principles for designing self-healing water-splitting catalysts are presented together with a formal kinetics model to account for the key chemical steps needed for self-healing. Self-healing may be realized if the catalysts are able to self-assemble at applied potentials less than that needed for catalyst turnover. Solution pH provides a convenient handle for controlling the potential of these two processes, as demonstrated for the cobalt phosphate (CoP<sub>i</sub>) water-splitting catalyst. Fo ...[more]

PMID: 28874551

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