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  • Role of perovskite thickness on optoelectronic properties in lead bromide and lead iodide thin film perovskites: A DFT study
Title: Role of perovskite thickness on optoelectronic properties in lead bromide and lead iodide thin film perovskites: A DFT study
Two-dimensional organic–inorganic hybrid lead halide perovskites are of interest for photovoltaic and light emitting devices due to their favorable properties that can be tuned. Here we use density functional theory to model two-dimensional lead halide perovskites of different thicknesses and using two different hallogens. Excited-state optoelectronic properties of the perovskite models are examined using excited-state dynamics treated by reduced density matrix method. Nonadiabatic couplings were computed based on the on-the-fly approach along a molecular dynamics trajectory at ambient temperatures. The density matrix-based equation of motion for electronic degrees of freedom was used to determine the dynamics of electronic degrees of freedom. We observe that the thickness of the perovskite layer shows a redshift in the absorption spectra with increasing thickness but has minimal effect on the photoluminescence quantum yield of the material.  more » « less
Award ID(s):
1944921 2004197
PAR ID:
10528766
Author(s) / Creator(s):
;
Publisher / Repository:
Materials Research Society
Date Published:
Journal Name:
MRS Advances
Volume:
8
Issue:
16
ISSN:
2059-8521
Page Range / eLocation ID:
901 to 906
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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