Additive-Free, Low-Temperature Crystallization of Stable α-FAPbI3 Perovskite

Additive-Free, Low-Temperature Crystallization of Stable α-FAPbI3 Perovskite

© 2022 The Authors. Advanced Materials published by Wiley-VCH GmbH.

Bibliographische Detailangaben
Veröffentlicht in:Advanced materials (Deerfield Beach, Fla.). - 1998. - 34(2022), 9 vom: 01. März, Seite e2107850
1. Verfasser: Du, Tian (VerfasserIn)
Weitere Verfasser: Macdonald, Thomas J, Yang, Ruo Xi, Li, Meng, Jiang, Zhongyao, Mohan, Lokeshwari, Xu, Weidong, Su, Zhenhuang, Gao, Xingyu, Whiteley, Richard, Lin, Chieh-Ting, Min, Ganghong, Haque, Saif A, Durrant, James R, Persson, Kristin A, McLachlan, Martyn A, Briscoe, Joe
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2022
Zugriff auf das übergeordnete Werk:Advanced materials (Deerfield Beach, Fla.)
Schlagworte:Journal Article additive-free aerosol-assisted crystallization formamidinium lead triiodide stability strain
Beschreibung
Zusammenfassung:© 2022 The Authors. Advanced Materials published by Wiley-VCH GmbH.
Formamidinium lead triiodide (FAPbI3 ) is attractive for photovoltaic devices due to its optimal bandgap at around 1.45 eV and improved thermal stability compared with methylammonium-based perovskites. Crystallization of phase-pure α-FAPbI3 conventionally requires high-temperature thermal annealing at 150 °C whilst the obtained α-FAPbI3 is metastable at room temperature. Here, aerosol-assisted crystallization (AAC) is reported, which converts yellow δ-FAPbI3 into black α-FAPbI3 at only 100 °C using precursor solutions containing only lead iodide and formamidinium iodide with no chemical additives. The obtained α-FAPbI3 exhibits remarkably enhanced stability compared to the 150 °C annealed counterparts, in combination with improvements in film crystallinity and photoluminescence yield. Using X-ray diffraction, X-ray scattering, and density functional theory simulation, it is identified that relaxation of residual tensile strains, achieved through the lower annealing temperature and post-crystallization crystal growth during AAC, is the key factor that facilitates the formation of phase-stable α-FAPbI3 . This overcomes the strain-induced lattice expansion that is known to cause the metastability of α-FAPbI3 . Accordingly, pure FAPbI3 p-i-n solar cells are reported, facilitated by the low-temperature (≤100 °C) AAC processing, which demonstrates increases of both power conversion efficiency and operational stability compared to devices fabricated using 150 °C annealed films
Beschreibung:Date Revised 03.03.2022
published: Print-Electronic
Citation Status PubMed-not-MEDLINE
ISSN:1521-4095
DOI:10.1002/adma.202107850