A Highly Emissive Surface Layer in Mixed-Halide Multication Perovskites.
Authors
Andaji-Garmaroudi, Zahra
Abdi-Jalebi, Mojtaba
Guo, Dengyang
Sadhanala, Aditya
Anaya, Miguel
Galkowski, Krzysztof
Lohmann, Kilian
Mackowski, Sebastian
Savenije, Tom J
Publication Date
2019-10Journal Title
Adv Mater
ISSN
0935-9648
Publisher
Wiley
Volume
31
Issue
42
Pages
e1902374
Language
eng
Type
Article
This Version
VoR
Physical Medium
Print-Electronic
Metadata
Show full item recordCitation
Andaji-Garmaroudi, Z., Abdi-Jalebi, M., Guo, D., Macpherson, S., Sadhanala, A., Tennyson, B., Ruggeri, E., et al. (2019). A Highly Emissive Surface Layer in Mixed-Halide Multication Perovskites.. Adv Mater, 31 (42), e1902374. https://doi.org/10.1002/adma.201902374
Abstract
Mixed-halide lead perovskites have attracted significant attention in the field of photovoltaics and other optoelectronic applications due to their promising bandgap tunability and device performance. Here, the changes in photoluminescence and photoconductance of solution-processed triple-cation mixed-halide (Cs0.06 MA0.15 FA0.79 )Pb(Br0.4 I0.6 )3 perovskite films (MA: methylammonium, FA: formamidinium) are studied under solar-equivalent illumination. It is found that the illumination leads to localized surface sites of iodide-rich perovskite intermixed with passivating PbI2 material. Time- and spectrally resolved photoluminescence measurements reveal that photoexcited charges efficiently transfer to the passivated iodide-rich perovskite surface layer, leading to high local carrier densities on these sites. The carriers on this surface layer therefore recombine with a high radiative efficiency, with the photoluminescence quantum efficiency of the film under solar excitation densities increasing from 3% to over 45%. At higher excitation densities, nonradiative Auger recombination starts to dominate due to the extremely high concentration of charges on the surface layer. This work reveals new insight into phase segregation of mixed-halide mixed-cation perovskites, as well as routes to highly luminescent films by controlling charge density and transfer in novel device structures.
Sponsorship
Lloyd's Register Foundation (via University of Southampton) (unknown)
European Research Council (756962)
Engineering and Physical Sciences Research Council (EP/P032591/1)
EPSRC (via Brunel University London) (unknown)
Royal Society (UF150033)
Engineering and Physical Sciences Research Council (EP/R023980/1)
European Commission Horizon 2020 (H2020) Marie Sk?odowska-Curie actions (841386)
Engineering and Physical Sciences Research Council (EP/M005143/1)
EPSRC (1948703)
Embargo Lift Date
2100-01-01
Identifiers
External DOI: https://doi.org/10.1002/adma.201902374
This record's URL: https://www.repository.cam.ac.uk/handle/1810/296227
Rights
Attribution 4.0 International (CC BY)
Licence URL: http://creativecommons.org/licenses/by/4.0/
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