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Modulation of Charge Recombination in CsPbBr₃ Perovskite Films with Electrochemical Bias.

ABSTRACT: The charging of a mesoscopic TiO₂ layer in a metal halide perovskite solar cell can influence the overall power conversion efficiency. By employing CsPbBr₃ films deposited on a mesoscopic TiO₂ film, we have succeeded in probing the influence of electrochemical bias on the charge carrier recombination process. The transient absorption spectroscopy experiments conducted at different applied potentials indicate a decrease in the charge carrier lifetimes of CsPbBr₃ as we increase the potential from -0.6 to +0.6 V vs Ag/AgCl. The charge carrier lifetime increased upon reversing the applied bias, thus indicating the reversibility of the photoresponse to charging effects. The ultrafast spectroelectrochemical experiments described here offer a convenient approach to probe the charging effects in perovskite solar cells.

SUBMITTER: Scheidt RA

PROVIDER: S-EPMC5765538 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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Modulation of Charge Recombination in CsPbBr3 Perovskite Films with Electrochemical Bias.

Scheidt Rebecca A RA Samu Gergely F GF Janáky Csaba C Kamat Prashant V PV

Journal of the American Chemical Society 20171121 1

The charging of a mesoscopic TiO2 layer in a metal halide perovskite solar cell can influence the overall power conversion efficiency. By employing CsPbBr3 films deposited on a mesoscopic TiO2 film, we have succeeded in probing the influence of electrochemical bias on the charge carrier recombination process. The transient absorption spectroscopy experiments conducted at different applied potentials indicate a decrease in the charge carrier lifetimes of CsPbBr<su ...[more]

PMID: 29129051

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