Interfacial electron accumulation for efficient homo-junction perovskite solar cells

Here we study perovskite solar cells based on mesoporous alumina scaffold infiltrated and capped with a perovskite absorber layer, which are devoid of a discrete n-type electron collection layer. We employ ethoxylated polyethylenimine (PEIE) to modify the interface between the perovskite absorber la...

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Main Authors: Song, S, Moon, B, Hörantner, M, Lim, J, Kang, G, Park, M, Kim, J, Snaith, H, Park, T
Format: Journal article
Published: Elsevier 2016
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author Song, S
Moon, B
Hörantner, M
Lim, J
Kang, G
Park, M
Kim, J
Snaith, H
Park, T
author_facet Song, S
Moon, B
Hörantner, M
Lim, J
Kang, G
Park, M
Kim, J
Snaith, H
Park, T
author_sort Song, S
collection OXFORD
description Here we study perovskite solar cells based on mesoporous alumina scaffold infiltrated and capped with a perovskite absorber layer, which are devoid of a discrete n-type electron collection layer. We employ ethoxylated polyethylenimine (PEIE) to modify the interface between the perovskite absorber layer and the metallic transparent fluorine-doped SnO 2 (FTO) electrode. Surprisingly, the PEIE interlayer obviates the requirement for the conventional dense-TiO 2 (d-TiO 2 ) compact layer (or organic fullerene layer), usually required to selectively extract electrons from the perovskite film. The self-organized PEIE interlayer produced a strong induced dipole moment at the perovskite-FTO interface, with our results indicating that electrons accumulate within the perovskite film at this interface. The resultant “n-type” contact region within the perovskite absorber layer, progressing to an intrinsic (i) region within the bulk of the perovskite layer, represents an n-i homojunction and favorably enables selective electron extraction at the FTO electrode. Resulting solar cells deliver current-voltage measured power conversion efficiencies (η) of over 15.0% and a substantial stabilized efficiency (η) of 9.1%. Although our solar cell performance remains lower than the highest reported efficiencies for perovskite solar cells employing discrete charge selective extraction layers, it indicates significant potential for “homo-junction” perovskite solar cells, once the metallic-to-perovskite contact is fully controlled. Additionally, our work identifies the potential impact of modifying the interface between the perovskite absorber and the subsequent contact materials with dipolar organic compounds, which may be applicable to optimizing contact at perovskite-semiconductor heterojunctions.
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spelling oxford-uuid:5b933ba2-d717-4c78-ab1f-3ce8d2adfc102022-03-26T17:22:53ZInterfacial electron accumulation for efficient homo-junction perovskite solar cellsJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:5b933ba2-d717-4c78-ab1f-3ce8d2adfc10Symplectic Elements at OxfordElsevier2016Song, SMoon, BHörantner, MLim, JKang, GPark, MKim, JSnaith, HPark, THere we study perovskite solar cells based on mesoporous alumina scaffold infiltrated and capped with a perovskite absorber layer, which are devoid of a discrete n-type electron collection layer. We employ ethoxylated polyethylenimine (PEIE) to modify the interface between the perovskite absorber layer and the metallic transparent fluorine-doped SnO 2 (FTO) electrode. Surprisingly, the PEIE interlayer obviates the requirement for the conventional dense-TiO 2 (d-TiO 2 ) compact layer (or organic fullerene layer), usually required to selectively extract electrons from the perovskite film. The self-organized PEIE interlayer produced a strong induced dipole moment at the perovskite-FTO interface, with our results indicating that electrons accumulate within the perovskite film at this interface. The resultant “n-type” contact region within the perovskite absorber layer, progressing to an intrinsic (i) region within the bulk of the perovskite layer, represents an n-i homojunction and favorably enables selective electron extraction at the FTO electrode. Resulting solar cells deliver current-voltage measured power conversion efficiencies (η) of over 15.0% and a substantial stabilized efficiency (η) of 9.1%. Although our solar cell performance remains lower than the highest reported efficiencies for perovskite solar cells employing discrete charge selective extraction layers, it indicates significant potential for “homo-junction” perovskite solar cells, once the metallic-to-perovskite contact is fully controlled. Additionally, our work identifies the potential impact of modifying the interface between the perovskite absorber and the subsequent contact materials with dipolar organic compounds, which may be applicable to optimizing contact at perovskite-semiconductor heterojunctions.
spellingShingle Song, S
Moon, B
Hörantner, M
Lim, J
Kang, G
Park, M
Kim, J
Snaith, H
Park, T
Interfacial electron accumulation for efficient homo-junction perovskite solar cells
title Interfacial electron accumulation for efficient homo-junction perovskite solar cells
title_full Interfacial electron accumulation for efficient homo-junction perovskite solar cells
title_fullStr Interfacial electron accumulation for efficient homo-junction perovskite solar cells
title_full_unstemmed Interfacial electron accumulation for efficient homo-junction perovskite solar cells
title_short Interfacial electron accumulation for efficient homo-junction perovskite solar cells
title_sort interfacial electron accumulation for efficient homo junction perovskite solar cells
work_keys_str_mv AT songs interfacialelectronaccumulationforefficienthomojunctionperovskitesolarcells
AT moonb interfacialelectronaccumulationforefficienthomojunctionperovskitesolarcells
AT horantnerm interfacialelectronaccumulationforefficienthomojunctionperovskitesolarcells
AT limj interfacialelectronaccumulationforefficienthomojunctionperovskitesolarcells
AT kangg interfacialelectronaccumulationforefficienthomojunctionperovskitesolarcells
AT parkm interfacialelectronaccumulationforefficienthomojunctionperovskitesolarcells
AT kimj interfacialelectronaccumulationforefficienthomojunctionperovskitesolarcells
AT snaithh interfacialelectronaccumulationforefficienthomojunctionperovskitesolarcells
AT parkt interfacialelectronaccumulationforefficienthomojunctionperovskitesolarcells