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  • Cesium Methylammonium Lead Iodide (Cs x MA 1−x PbI 3 ) Nanocrystals with Wide Range Cation Composition Tuning and Enhanced Thermal Stability of the Perovskite Phase
Title: Cesium Methylammonium Lead Iodide (Cs x MA 1−x PbI 3 ) Nanocrystals with Wide Range Cation Composition Tuning and Enhanced Thermal Stability of the Perovskite Phase
Abstract Cesium methylammonium lead iodide (CsxMA1−xPbI3) nanocrystals were obtained with a wide range of A‐site Cs‐MA compositions by post‐synthetic, room temperature cation exchange between CsPbI3nanocrystals and MAPbI3nanocrystals. The alloyed CsxMA1−xPbI3nanocrystals retain their photoactive perovskite phase with incorporated Cs content,x, as high as 0.74 and the expected composition‐tunable photoluminescence (PL). Excess methylammonium oleate from the reaction mixture in the MAPbI3nanocrystal dispersions was necessary to obtain fast Cs‐MA cation exchange. The phase transformation and degradation kinetics of films of CsxMA1−xPbI3nanocrystals were measured and modeled using an Avrami expression. The transformation kinetics were significantly slower than those of the parent CsPbI3and MAPbI3nanocrystals, with Avrami rate constants,k, at least an order of magnitude smaller. These results affirm that A‐site cation alloying is a promising strategy for stabilizing iodide‐based perovskites.  more » « less
Award ID(s):
1720595 2052814
PAR ID:
10509912
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
Wiley-VCH
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
62
Issue:
31
ISSN:
1433-7851
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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