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Title: Polystyrene‐based Macromolecular Ammonium Halides for Tuning Color and Exchange Kinetics of Perovskite Nanocrystals
Abstract

Post‐synthesis anion exchange of all‐inorganic cesium lead halide perovskite nanocrystals (CsPbX3NCs, where X=Cl, Br, and/or I) provides a rapid and simple means of tuning their band gap and photoluminescence emission wavelengths. Here we report color‐shifting of CsPbX3nanocrystals induced by a macromolecular source of halide ions, specifically using polystyrene with ammonium halides as pendent groups. This strategy for introducing new halides to the perovskite nanocrystals gave access to perovskite‐polymer hybrid materials as solutions, thin films, or free‐flowing powders. Spectroscopic measurements of the halide‐exchanged nanocrystal products revealed high photoluminescence quantum yields across the visible spectrum, with exchange kinetics that were tunable based on the solution environment, suggesting an aggregation‐inhibited exchange process that affords access to multi‐colored solutions and films.

 
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NSF-PAR ID:
10370707
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
61
Issue:
37
ISSN:
1433-7851
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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