Lewis base passivation mediates charge transfer at perovskite heterojunctions
File(s)
Accepted version
Author(s)
Type
Journal Article
Abstract
Understanding interfacial charge transfer processes such as trap-mediated recombination
and injection into charge transport layers (CTLs) is crucial for the improvement of perovskite
solar cells. Herein, we reveal that the chemical binding of charge transport layers to
CH3NH3PbI3 defect sites is an integral part of the interfacial charge injection mechanism in
both n-i-p and p-i-n architectures. Specifically, we use a mixture of optical and X-Ray
photoelectron spectroscopy to show that binding interactions occur via Lewis base
interactions between electron donating moieties on hole transport layers and the
CH3NH3PbI3 surface. We then correlate the extent of binding with an improvement in the
yield and longer lifetime of injected holes with transient absorption spectroscopy. Our
results show that passivation-mediated charge transfer has been occurring undetected in
some of the most common perovskite configurations and elucidate a key design rule for the
chemical structure of next-generation CTLs.
and injection into charge transport layers (CTLs) is crucial for the improvement of perovskite
solar cells. Herein, we reveal that the chemical binding of charge transport layers to
CH3NH3PbI3 defect sites is an integral part of the interfacial charge injection mechanism in
both n-i-p and p-i-n architectures. Specifically, we use a mixture of optical and X-Ray
photoelectron spectroscopy to show that binding interactions occur via Lewis base
interactions between electron donating moieties on hole transport layers and the
CH3NH3PbI3 surface. We then correlate the extent of binding with an improvement in the
yield and longer lifetime of injected holes with transient absorption spectroscopy. Our
results show that passivation-mediated charge transfer has been occurring undetected in
some of the most common perovskite configurations and elucidate a key design rule for the
chemical structure of next-generation CTLs.
Date Issued
2021-08-11
Date Acceptance
2021-07-09
Citation
Journal of the American Chemical Society, 2021, 143 (31), pp.12230-12243
ISSN
0002-7863
Publisher
American Chemical Society
Start Page
12230
End Page
12243
Journal / Book Title
Journal of the American Chemical Society
Volume
143
Issue
31
Copyright Statement
Copyright reserved
© 2021 American Chemical Society.
Sponsor
Engineering and Physical Sciences Research Council
Engineering & Physical Science Research Council (EPSRC)
Royal Commission for the Exhibition of 1851
Grant Number
EP/L015277/1
EP/R020574/1
CHSA_P82337
Subjects
General Chemistry
03 Chemical Sciences
Publication Status
Published
Date Publish Online
2021-08-03