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  • Effects of Surface Defects on Performance and Dynamics of CsPbI 2 Br Perovskite: First-Principles Nonadiabatic Molecular Dynamics Simulations
Title: Effects of Surface Defects on Performance and Dynamics of CsPbI 2 Br Perovskite: First-Principles Nonadiabatic Molecular Dynamics Simulations
Inorganic mixed-halogen perovskites exhibit excellent photovoltaic properties and stability; yet, their photoelectric conversion efficiency is limited by inherent surface defects. In this work, we study the impact of defects on properties of CsPbI2Br slabs using first-principles calculations, focusing on specific defects such as I vacancy (VI), I interposition (Ii), and I substitution by Pb (PbI). Our findings reveal that these defects affect the geometric and optoelectronic properties as well as dynamics of charge carriers of slabs. We employ two theoretical frameworks (surface hopping and Redfield theory) of nonadiabatic molecular dynamics simulations to comprehensively study relaxation processes and obtain consistent results. The presence of VI reduces carrier lifetimes, while the influence of PbI on carrier lifetimes is negligible. In contrast, Ii defects lead to prolonged carrier lifetimes. These insights provide valuable guidance for the rational design of perovskite photovoltaic devices, aiming to enhance their efficiency and stability.  more » « less
Award ID(s):
1944921
PAR ID:
10528716
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
American Chemical Society
Date Published:
Journal Name:
The Journal of Physical Chemistry Letters
Volume:
15
Issue:
18
ISSN:
1948-7185
Page Range / eLocation ID:
4782 to 4791
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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