Cargando…

Chlorine activated stacking fault removal mechanism in thin film CdTe solar cells: the missing piece

The conversion efficiency of as-deposited, CdTe solar cells is poor and typically less than 5%. A CdCl(2) activation treatment increases this to up to 22%. Studies have shown that stacking faults (SFs) are removed and the grain boundaries (GBs) are decorated with chlorine. Thus, SF removal and devic...

Descripción completa

Detalles Bibliográficos
Autores principales: Hatton, Peter, Watts, Michael J., Abbas, Ali, Walls, John M., Smith, Roger, Goddard, Pooja
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Nature Publishing Group UK 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8382740/
https://www.ncbi.nlm.nih.gov/pubmed/34426582
http://dx.doi.org/10.1038/s41467-021-25063-y
_version_ 1783741599286558720
author Hatton, Peter
Watts, Michael J.
Abbas, Ali
Walls, John M.
Smith, Roger
Goddard, Pooja
author_facet Hatton, Peter
Watts, Michael J.
Abbas, Ali
Walls, John M.
Smith, Roger
Goddard, Pooja
author_sort Hatton, Peter
collection PubMed
description The conversion efficiency of as-deposited, CdTe solar cells is poor and typically less than 5%. A CdCl(2) activation treatment increases this to up to 22%. Studies have shown that stacking faults (SFs) are removed and the grain boundaries (GBs) are decorated with chlorine. Thus, SF removal and device efficiency are strongly correlated but whether this is direct or indirect has not been established. Here we explain the passivation responsible for the increase in efficiency but also crucially elucidate the associated SF removal mechanism. The effect of chlorine on a model system containing a SF and two GBs is investigated using density functional theory. The proposed SF removal mechanisms are feasible at the 400 (∘)C treatment temperature. It is concluded that the efficiency increase is due to electronic effects in the GBs while SF removal is a by-product of the saturation of the GB with chlorine but is a key signal that sufficient chlorine is present for passivation to occur.
format Online
Article
Text
id pubmed-8382740
institution National Center for Biotechnology Information
language English
publishDate 2021
publisher Nature Publishing Group UK
record_format MEDLINE/PubMed
spelling pubmed-83827402021-09-22 Chlorine activated stacking fault removal mechanism in thin film CdTe solar cells: the missing piece Hatton, Peter Watts, Michael J. Abbas, Ali Walls, John M. Smith, Roger Goddard, Pooja Nat Commun Article The conversion efficiency of as-deposited, CdTe solar cells is poor and typically less than 5%. A CdCl(2) activation treatment increases this to up to 22%. Studies have shown that stacking faults (SFs) are removed and the grain boundaries (GBs) are decorated with chlorine. Thus, SF removal and device efficiency are strongly correlated but whether this is direct or indirect has not been established. Here we explain the passivation responsible for the increase in efficiency but also crucially elucidate the associated SF removal mechanism. The effect of chlorine on a model system containing a SF and two GBs is investigated using density functional theory. The proposed SF removal mechanisms are feasible at the 400 (∘)C treatment temperature. It is concluded that the efficiency increase is due to electronic effects in the GBs while SF removal is a by-product of the saturation of the GB with chlorine but is a key signal that sufficient chlorine is present for passivation to occur. Nature Publishing Group UK 2021-08-23 /pmc/articles/PMC8382740/ /pubmed/34426582 http://dx.doi.org/10.1038/s41467-021-25063-y Text en © The Author(s) 2021, corrected publication 2022 https://creativecommons.org/licenses/by/4.0/Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/ (https://creativecommons.org/licenses/by/4.0/) .
spellingShingle Article
Hatton, Peter
Watts, Michael J.
Abbas, Ali
Walls, John M.
Smith, Roger
Goddard, Pooja
Chlorine activated stacking fault removal mechanism in thin film CdTe solar cells: the missing piece
title Chlorine activated stacking fault removal mechanism in thin film CdTe solar cells: the missing piece
title_full Chlorine activated stacking fault removal mechanism in thin film CdTe solar cells: the missing piece
title_fullStr Chlorine activated stacking fault removal mechanism in thin film CdTe solar cells: the missing piece
title_full_unstemmed Chlorine activated stacking fault removal mechanism in thin film CdTe solar cells: the missing piece
title_short Chlorine activated stacking fault removal mechanism in thin film CdTe solar cells: the missing piece
title_sort chlorine activated stacking fault removal mechanism in thin film cdte solar cells: the missing piece
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8382740/
https://www.ncbi.nlm.nih.gov/pubmed/34426582
http://dx.doi.org/10.1038/s41467-021-25063-y
work_keys_str_mv AT hattonpeter chlorineactivatedstackingfaultremovalmechanisminthinfilmcdtesolarcellsthemissingpiece
AT wattsmichaelj chlorineactivatedstackingfaultremovalmechanisminthinfilmcdtesolarcellsthemissingpiece
AT abbasali chlorineactivatedstackingfaultremovalmechanisminthinfilmcdtesolarcellsthemissingpiece
AT wallsjohnm chlorineactivatedstackingfaultremovalmechanisminthinfilmcdtesolarcellsthemissingpiece
AT smithroger chlorineactivatedstackingfaultremovalmechanisminthinfilmcdtesolarcellsthemissingpiece
AT goddardpooja chlorineactivatedstackingfaultremovalmechanisminthinfilmcdtesolarcellsthemissingpiece