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Title: Influence of Charge Transport Layers on Capacitance Measured in Halide Perovskite Solar Cells
Capacitance-based techniques have been used to measure the electrical properties of halide perovskite solar cells (PSCs) such as defect activation energy and density, carrier concentration, and dielectric constant, which provide key information for evaluating the device performance. Here, we show that capacitance-based techniques cannot be used to reliably analyze the properties of defects in the perovskite layer or at its interface, since the high-frequency capacitance signature is due to the response of charge carriers in the hole-transport layer (HTL). For HTL-free PSCs, the high-frequency capacitance can be considered as the geometric capacitance for analyzing the dielectric constant of the perovskite layer, since there is no trapping and de-trapping of charge carriers in the perovskite layer. We further find that the low-frequency capacitance signature can be used to calculate the activation energy of the ionic conductivity of the perovskite layer, but the overlapping effects with charge transport materials must be avoided.  more » « less
Award ID(s):
1807818
PAR ID:
10157086
Author(s) / Creator(s):
Date Published:
Journal Name:
Joule
Volume:
4
Issue:
3
ISSN:
2542-4785
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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