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The correlation between phase transition and photoluminescence properties of CsPbX₃ (X= Cl, Br, I) perovskite nanocrystals.

ABSTRACT: We report a correlation between the structural phase transition of CsPbX₃ (X=Cl, Br, I) nanocrystals (NCs) and their temperature dependent steady-state photoluminescence (PL) and time-resolved PL (TRPL). In constrast to CsPbBr₃ and CsPbI₃ NCs which exhibited a continuous blue shift in their bandgap with increasing temperature, the CsPbCl₃ exhibited a blue shift until ~193 K, followed by a red shift until room temperature. We attribute this change from a blue to a red shift to a structural phase transtion in CsPbCl₃, which also manifested in the temperature dependent TRPL. Notably, the exciton recombination lifetimes showed a similar reverse trend due to the phase transition in CsPbCl₃, which has not been reported previously.

SUBMITTER: Yi J

PROVIDER: S-EPMC8290899 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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The correlation between phase transition and photoluminescence properties of CsPbX3 (X= Cl, Br, I) perovskite nanocrystals.

Yi Jun J Ge Xueying X Liu Exian E Cai Tong T Zhao Chujun C Wen Shuangchun S Sanabria Hugo H Chen Ou O Rao Apparao M AM Gao Jianbo J

Nanoscale advances 20200706 10

We report a correlation between the structural phase transition of CsPbX3 (X=Cl, Br, I) nanocrystals (NCs) and their temperature dependent steady-state photoluminescence (PL) and time-resolved PL (TRPL). In constrast to CsPbBr3 and CsPbI3 NCs which exhibited a continuous blue shift in their bandgap with increasing temperature, the CsPbCl3 exhibited a blue shift until ~193 K, followed by a red shift until room temperature. We attribute this change from ...[more]

PMID: 34291189

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