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Tuning the Excited-State Dynamics of CuI Films with Electrochemical Bias.

ABSTRACT: Owing to its high hole conductivity and ease of preparation, CuI was among the first inorganic hole-transporting materials that were introduced early on in metal halide perovskite solar cells, but its full potential as a semiconductor material is still to be realized. We have now performed ultrafast spectroelectrochemical experiments on ITO/CuI electrodes to show the effect of applied bias on the excited-state dynamics in CuI. Under operating conditions, the recombination of excitons is dependent on the applied bias, and it can be accelerated by decreasing the potential from +0.6 to -0.1 V vs Ag/AgCl. Prebiasing experiments show the persistent and reversible "memory" effect of electrochemical bias on charge carrier lifetimes. The excitation of CuI in a CuI/CsPbBr3 film provides synergy between both CuI and CsPbBr3 in dictating the charge separation and recombination.

SUBMITTER: Samu GF

PROVIDER: S-EPMC6413481 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Tuning the Excited-State Dynamics of CuI Films with Electrochemical Bias.

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

ACS energy letters 20190213 3

Owing to its high hole conductivity and ease of preparation, CuI was among the first inorganic hole-transporting materials that were introduced early on in metal halide perovskite solar cells, but its full potential as a semiconductor material is still to be realized. We have now performed ultrafast spectroelectrochemical experiments on ITO/CuI electrodes to show the effect of applied bias on the excited-state dynamics in CuI. Under operating conditions, the recombination of excitons is dependen ...[more]

PMID: 30882041

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