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Investigation of Cation Exchange Behaviors of FAxMA1-xPbI3 Films Using Dynamic Spin-Coating.

ABSTRACT: In this study, we fabricated and characterized uniform multi-cation perovskite FAxMA1-xPbI3 films. We used the dynamic spin-coating method to control the cation ratio of the film by gradually increasing the FA+, which replaced the MA+ in the films. When the FA+ concentration was lower than xFA ~0.415 in the films, the stability of the multi-cation perovskite improved. Above this concentration, the film exhibited δ-phase FAPbI3 in the FAxMA1-xPbI3 films. The formation of δ-phase FAPbI3 disturbed the homogeneity of the photoluminescence spatial distribution and suppressed the absorption spectral bandwidth with the increasing bandgap. The precise control of the cation ratio of multi-cation perovskite films is necessary to optimize the energy-harvesting performance.

SUBMITTER: Yu HM

PROVIDER: S-EPMC8585367 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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Investigation of Cation Exchange Behaviors of FAxMA1-xPbI3 Films Using Dynamic Spin-Coating.

Yu Hyang Mi HM Jeong Byeong Geun BG Park Dae Young DY Lim Seong Chu SC Namkoong Gon G Jeong Mun Seok MS

Materials (Basel, Switzerland) 20211026 21

In this study, we fabricated and characterized uniform multi-cation perovskite FAxMA1-xPbI3 films. We used the dynamic spin-coating method to control the cation ratio of the film by gradually increasing the FA+, which replaced the MA+ in the films. When the FA+ concentration was lower than xFA ~0.415 in the films, the stability of the multi-cation perovskite improved. Above this concentration, the film exhibited δ-phase FAPbI3 in the FAxMA<s ...[more]

PMID: 34771948

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