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Title: Hybrid Perovskite Phase Transition and Its Ionic, Electrical and Optical Properties
ABSTRACT Hybrid perovskite solar cells (PSCs) under normal operation will reach a temperature above ∼ 60 °C, across the tetragonal-cubic structural phase transition of methylammonium lead iodide (MAPbI 3 ). Whether the structural phase transition could result in dramatic changes of ionic, electrical and optical properties that may further impact the PSC performances should be studied. Herein, we report a structural phase transition temperature of MAPbI 3 thin film at ∼ 55 °C, but a striking contrast occurred at ∼ 45 °C in the ionic and electrical properties of MAPbI 3 due to a change of the ion activation energy from 0.7 eV to 0.5 eV. The optical properties exhibited no sharp transition except for the steady increase of the bandgap with temperature. It was also observed that the activation energy for ionic migration steadily increased with increased grain sizes, and reduction of the grain boundary density reduced the ionic migration.  more » « less
Award ID(s):
1438681
PAR ID:
10091600
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
MRS Advances
Volume:
2
Issue:
53
ISSN:
2059-8521
Page Range / eLocation ID:
3077 to 3082
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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