How Photogenerated I2 Induces I-Rich Phase Formation in Lead Mixed Halide Perovskites

How Photogenerated I2 Induces I-Rich Phase Formation in Lead Mixed Halide Perovskites

© 2023 The Authors. Advanced Materials published by Wiley-VCH GmbH.

Bibliographische Detailangaben
Veröffentlicht in:Advanced materials (Deerfield Beach, Fla.). - 1998. - 36(2024), 1 vom: 24. Jan., Seite e2305567
1. Verfasser: Zhou, Yang (VerfasserIn)
Weitere Verfasser: van Laar, Simone C W, Meggiolaro, Daniele, Gregori, Luca, Martani, Samuele, Heng, Jia-Yong, Datta, Kunal, Jiménez-López, Jesús, Wang, Feng, Wong, E Laine, Poli, Isabella, Treglia, Antonella, Cortecchia, Daniele, Prato, Mirko, Kobera, Libor, Gao, Feng, Zhao, Ni, Janssen, René A J, De Angelis, Filippo, Petrozza, Annamaria
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2024
Zugriff auf das übergeordnete Werk:Advanced materials (Deerfield Beach, Fla.)
Schlagworte:Journal Article defects metal halide semiconductors optoelectronics solar cells wide bandgap metal halide perovskites
Beschreibung
Zusammenfassung:© 2023 The Authors. Advanced Materials published by Wiley-VCH GmbH.
Bandgap tunability of lead mixed halide perovskites (LMHPs) is a crucial characteristic for versatile optoelectronic applications. Nevertheless, LMHPs show the formation of iodide-rich (I-rich) phase under illumination, which destabilizes the semiconductor bandgap and impedes their exploitation. Here, it is shown that how I2 , photogenerated upon charge carrier trapping at iodine interstitials in LMHPs, can promote the formation of I-rich phase. I2 can react with bromide (Br- ) in the perovskite to form a trihalide ion I2 Br- (Iδ- -Iδ+ -Brδ- ), whose negatively charged iodide (Iδ- ) can further exchange with another lattice Br- to form the I-rich phase. Importantly, it is observed that the effectiveness of the process is dependent on the overall stability of the crystalline perovskite structure. Therefore, the bandgap instability in LMHPs is governed by two factors, i.e., the density of native defects leading to I2 production and the Br- binding strength within the crystalline unit. Eventually, this study provides rules for the design of chemical composition in LMHPs to reach their full potential for optoelectronic devices
Beschreibung:Date Revised 04.01.2024
published: Print-Electronic
Citation Status PubMed-not-MEDLINE
ISSN:1521-4095
DOI:10.1002/adma.202305567