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  • Dielectric constants and double-layer formation in a perovskite thin film revealed by electrochemical impedance spectroscopy
Title: Dielectric constants and double-layer formation in a perovskite thin film revealed by electrochemical impedance spectroscopy
Hybrid perovskites have attracted great interest in solar energy conversion and optoelectronic applications. The interconnected ionic and electronic effects complicate assessing the underlying electrical processes while contributing greatly to the efficiency and stability of devices. Fortunately, these coupled processes manifest on distinct timescales that enable frequency-specific electrochemical analysis. However, hybrid perovskites dissolve in most of the common aqueous and organic solvents utilized for electrochemistry. Here, we utilize a hydrofluoroether (HFE) solvent toolkit to perform nondestructive electrochemical impedance spectroscopy of methylammonium lead iodide (MAPbI3) perovskite thin films. This enables the extraction of dielectric constants and double-layer formation in these perovskite films.  more » « less
Award ID(s):
1906505
PAR ID:
10484003
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Springer
Date Published:
Journal Name:
MRS Communications
ISSN:
2159-6867
Subject(s) / Keyword(s):
Electrical properties Ion conductor Optoelectronic Thin film Electronic material
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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