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Light-induced water oxidation at silicon electrodes functionalized with a cobalt oxygen-evolving catalyst.

ABSTRACT: Integrating a silicon solar cell with a recently developed cobalt-based water-splitting catalyst (Co-Pi) yields a robust, monolithic, photo-assisted anode for the solar fuels process of water splitting to O(2) at neutral pH. Deposition of the Co-Pi catalyst on the Indium Tin Oxide (ITO)-passivated p-side of a np-Si junction enables the majority of the voltage generated by the solar cell to be utilized for driving the water-splitting reaction. Operation under neutral pH conditions fosters enhanced stability of the anode as compared to operation under alkaline conditions (pH 14) for which long-term stability is much more problematic. This demonstration of a simple, robust construct for photo-assisted water splitting is an important step towards the development of inexpensive direct solar-to-fuel energy conversion technologies.

SUBMITTER: Pijpers JJ

PROVIDER: S-EPMC3121807 | biostudies-other | 2011 Jun

REPOSITORIES: biostudies-other

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Light-induced water oxidation at silicon electrodes functionalized with a cobalt oxygen-evolving catalyst.

Pijpers Joep J H JJ Winkler Mark T MT Surendranath Yogesh Y Buonassisi Tonio T Nocera Daniel G DG

Proceedings of the National Academy of Sciences of the United States of America 20110606 25

Integrating a silicon solar cell with a recently developed cobalt-based water-splitting catalyst (Co-Pi) yields a robust, monolithic, photo-assisted anode for the solar fuels process of water splitting to O(2) at neutral pH. Deposition of the Co-Pi catalyst on the Indium Tin Oxide (ITO)-passivated p-side of a np-Si junction enables the majority of the voltage generated by the solar cell to be utilized for driving the water-splitting reaction. Operation under neutral pH conditions fosters enhance ...[more]

PMID: 21646536

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