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Potentiometric Measurements of Semiconductor Nanocrystal Redox Potentials.

ABSTRACT: A potentiometric method for measuring redox potentials of colloidal semiconductor nanocrystals (NCs) is described. Fermi levels of colloidal ZnO NCs are measured in situ during photodoping, allowing correlation of NC redox potentials and reduction levels. Excellent agreement is found between electrochemical and optical redox-indicator methods. Potentiometry is also reported for colloidal CdSe NCs, which show more negative conduction-band-edge potentials than in ZnO. This difference is highlighted by spontaneous electron transfer from reduced CdSe NCs to ZnO NCs in solution, with potentiometry providing a measure of the inter-NC electron-transfer driving force. Future applications of NC potentiometry are briefly discussed.

SUBMITTER: Carroll GM

PROVIDER: S-EPMC5107322 | biostudies-literature | 2016 Apr

REPOSITORIES: biostudies-literature

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Potentiometric Measurements of Semiconductor Nanocrystal Redox Potentials.

Carroll Gerard M GM Brozek Carl K CK Hartstein Kimberly H KH Tsui Emily Y EY Gamelin Daniel R DR

Journal of the American Chemical Society 20160323 13

A potentiometric method for measuring redox potentials of colloidal semiconductor nanocrystals (NCs) is described. Fermi levels of colloidal ZnO NCs are measured in situ during photodoping, allowing correlation of NC redox potentials and reduction levels. Excellent agreement is found between electrochemical and optical redox-indicator methods. Potentiometry is also reported for colloidal CdSe NCs, which show more negative conduction-band-edge potentials than in ZnO. This difference is highlighte ...[more]

PMID: 26978480

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