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Title: The use of ion-selective membranes to study cation transport in hybrid organic–inorganic perovskites
Using a methylammonium selective membrane in conjunction with electrochemical impedance spectroscopy, we measured ion migration in methylammonium lead triiodide (MAPbI 3 ) with a millisecond (ms) time constant under illumination. These values were consistent with the reported values of ionic conduction in thin-film perovskite solar cells. We monitored an electrochemical impedance response arising from ionic conductivity through MAPbI 3 and a methylammonium selective layer. We could fit this complex impedance response to an intuitive circuit model, which revealed an ionic species moving on a ms time scale. Electrospray ionization mass spectrometry (ESI-MS) revealed direct chemical evidence of methylammonium diffusion into the ion-selective layer. We found no experimental evidence indicating the mobility of lead ions or protons, suggesting that the mobile species observed under illumination is likely methylammonium.  more » « less
Award ID(s):
1726578
PAR ID:
10181583
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Physical Chemistry Chemical Physics
Volume:
21
Issue:
37
ISSN:
1463-9076
Page Range / eLocation ID:
20720 to 20726
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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