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Time-Resolved Raman Spectroscopy of Polaron Formation in a Polymer Photocatalyst.

ABSTRACT: Polymer photocatalysts are a synthetically diverse class of materials that can be used for the production of solar fuels such as H₂, but the underlying mechanisms by which they operate are poorly understood. Time-resolved vibrational spectroscopy provides a powerful structure-specific probe of photogenerated species. Here we report the use of time-resolved resonance Raman (TR³) spectroscopy to study the formation of polaron pairs and electron polarons in one of the most active linear polymer photocatalysts for H₂ production, poly(dibenzo[b,d]thiophene sulfone), P10. We identify that polaron-pair formation prior to thermalization of the initially generated excited states is an important pathway for the generation of long-lived photoelectrons.

SUBMITTER: Piercy VL

PROVIDER: S-EPMC8591663 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature

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Time-Resolved Raman Spectroscopy of Polaron Formation in a Polymer Photocatalyst.

Piercy Verity L VL Saeed Khezar H KH Prentice Andrew W AW Neri Gaia G Li Chao C Gardner Adrian M AM Bai Yang Y Sprick Reiner Sebastian RS Sazanovich Igor V IV Cooper Andrew I AI Rosseinsky Matthew J MJ Zwijnenburg Martijn A MA Cowan Alexander J AJ

The journal of physical chemistry letters 20211103 44

Polymer photocatalysts are a synthetically diverse class of materials that can be used for the production of solar fuels such as H<sub>2</sub>, but the underlying mechanisms by which they operate are poorly understood. Time-resolved vibrational spectroscopy provides a powerful structure-specific probe of photogenerated species. Here we report the use of time-resolved resonance Raman (TR<sup>3</sup>) spectroscopy to study the formation of polaron pairs and electron polarons in one of the most act ...[more]

PMID: 34730969

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Dataset Information

Time-Resolved Raman Spectroscopy of Polaron Formation in a Polymer Photocatalyst.

Publications

Time-Resolved Raman Spectroscopy of Polaron Formation in a Polymer Photocatalyst.

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