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Fluorescent Alloy CsPb x Mn1-x I3 Perovskite Nanocrystals with High Structural and Optical Stability.

ABSTRACT: CsPbI3 nanocrystals are still limited in their use because of their phase instability as they degrade into the yellow nonemitting ?-CsPbI3 phase within a few days. We show that alloyed CsPb x Mn1-x I3 nanocrystals have essentially the same optical features and crystal structure as the parent ?-CsPbI3 system, but they are stable in films and in solution for periods over a month. The stabilization stems from a small decrease in the lattice parameters slightly increasing the Goldsmith tolerance factor, combined with an increase in the cohesive energy. Finally, hybrid density functional calculations confirm that the Mn2+ levels fall within the conduction band, thus not strongly altering the optical properties.

SUBMITTER: Akkerman QA

PROVIDER: S-EPMC5679661 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

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Fluorescent Alloy CsPb x Mn1-x I3 Perovskite Nanocrystals with High Structural and Optical Stability.

Akkerman Quinten A QA Meggiolaro Daniele D Dang Zhiya Z De Angelis Filippo F Manna Liberato L

ACS energy letters 20170828 9

CsPbI3 nanocrystals are still limited in their use because of their phase instability as they degrade into the yellow nonemitting δ-CsPbI3 phase within a few days. We show that alloyed CsPb x Mn1-x I3 nanocrystals have essentially the same optical features and crystal structure as the parent α-CsPbI3 system, but they are stable in films and in solution for periods over a month. The stabilization stems from a small de ...[more]

PMID: 29142911

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