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Inorganic A-site cations improve the performance of band-edge carriers in lead halide perovskites.

ABSTRACT: In lead halide perovskites, organic A-site cations are generally introduced to fine-tune the properties. One of the questions under debate is whether organic A-site cations are essential for high-performance solar cells. In this study, we compare the band edge carrier dynamics and diffusion process in MAPbBr₃ and CsPbBr₃ single-crystal microplates. By transient absorption microscopy, the band-edge carrier diffusion constants are unraveled. With the replacement of inorganic A-site cations, the diffusion constant in CsPbBr₃ increases almost 8 times compared to that in MAPbBr₃. This work reveals that introducing inorganic A-site cations can lead to a much larger diffusion length and improve the performance of band-edge carriers.

SUBMITTER: Wang C

PROVIDER: S-EPMC10519920 | biostudies-literature | 2023 Sep

REPOSITORIES: biostudies-literature

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Inorganic A-site cations improve the performance of band-edge carriers in lead halide perovskites.

Wang Cheng C Rong Yaoguang Y Wang Ti T

Frontiers of optoelectronics 20230925 1

In lead halide perovskites, organic A-site cations are generally introduced to fine-tune the properties. One of the questions under debate is whether organic A-site cations are essential for high-performance solar cells. In this study, we compare the band edge carrier dynamics and diffusion process in MAPbBr<sub>3</sub> and CsPbBr<sub>3</sub> single-crystal microplates. By transient absorption microscopy, the band-edge carrier diffusion constants are unraveled. With the replacement of inorganic ...[more]

PMID: 37747592

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