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  • Metal Halide Perovskite Nanocrystals for Near-Infrared Circularly Polarized Luminescence with High Photoluminescence Quantum Yield via Chiral Ligand Exchange
Title: Metal Halide Perovskite Nanocrystals for Near-Infrared Circularly Polarized Luminescence with High Photoluminescence Quantum Yield via Chiral Ligand Exchange
Using ligand exchange on FAPbI3 perovskite nanocrystals (PNCs) surface with chiral tridentate L-cysteine (Lcys) ligand, we successfully prepared chiral FAPbI3 PNCs that show circularly polarized luminescence (CPL) (dissymmetry factor; glum = 2.1 × 10−3) in the near-infrared (NIR) region from 700 to 850 nm and a photoluminescence quantum yield (PLQY) of 81%. The chiral characteristics of FAPbI3 PNCs are ascribed to induction by chiral L/D-cys, and the high PLQY is attributed to the passivation of the PNCs defects with L-cys. Also, effective passivation of defects on the surface of FAPbI3 PNCs by L-cys results in excellent stability toward atmospheric water and oxygen. The conductivity of the L-cys treated FAPbI3 NC films is improved, which is attributed to the partial substitution of L-cys for the insulating long oleyl ligand. The CPL of the L-cys ligand treated FAPbI3 PNCs film retains a glum of −2.7 × 10−4. This study demonstrates a facile yet effective approach to generating chiral PNCs with CPL for NIR photonics applications.  more » « less
Award ID(s):
2203633
PAR ID:
10537516
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
ACS
Date Published:
Journal Name:
The Journal of Physical Chemistry Letters
Volume:
14
Issue:
24
ISSN:
1948-7185
Page Range / eLocation ID:
5489 to 5496
Subject(s) / Keyword(s):
perovskite nanocrystals circularly polarized luminescence
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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