Nonradiative Energy Losses in Bulk-Heterojunction Organic Photovoltaics

The performance of solar cells based on molecular electronic materials is limited by relatively high nonradiative voltage losses. The primary pathway for nonradiative recombination in organic donor-acceptor heterojunction devices is believed to be the decay of a charge-transfer (CT) excited state to...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Mohammed Azzouzi, Jun Yan, Thomas Kirchartz, Kaikai Liu, Jinliang Wang, Hongbin Wu, Jenny Nelson
Formato:	article
Lenguaje:	EN
Publicado:	American Physical Society 2018
Materias:	Physics QC1-999
Acceso en línea:	https://doaj.org/article/cb8ca1d8600d4e44858d19bba5e91a4e
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:doaj.org-article:cb8ca1d8600d4e44858d19bba5e91a4e
record_format	dspace
spelling	oai:doaj.org-article:cb8ca1d8600d4e44858d19bba5e91a4e2021-12-02T11:49:59ZNonradiative Energy Losses in Bulk-Heterojunction Organic Photovoltaics10.1103/PhysRevX.8.0310552160-3308https://doaj.org/article/cb8ca1d8600d4e44858d19bba5e91a4e2018-09-01T00:00:00Zhttp://doi.org/10.1103/PhysRevX.8.031055http://doi.org/10.1103/PhysRevX.8.031055https://doaj.org/toc/2160-3308The performance of solar cells based on molecular electronic materials is limited by relatively high nonradiative voltage losses. The primary pathway for nonradiative recombination in organic donor-acceptor heterojunction devices is believed to be the decay of a charge-transfer (CT) excited state to the ground state via energy transfer to vibrational modes. Recently, nonradiative voltage losses have been related to properties of the charge-transfer state such as the Franck-Condon factor describing the overlap of the CT and ground-state vibrational states and, therefore, to the energy of the CT state. However, experimental data do not always follow the trends suggested by the simple model. Here, we extend this recombination model to include other factors that influence the nonradiative decay-rate constant, and therefore the open-circuit voltage, but have not yet been explored in detail. We use the extended model to understand the observed behavior of series of small molecules:fullerene blend devices, where open-circuit voltage appears insensitive to nonradiative loss. The trend could be explained only in terms of a microstructure-dependent CT-state oscillator strength, showing that parameters other than CT-state energy can control nonradiative recombination. We present design rules for improving open-circuit voltage via the control of material parameters and propose a realistic limit to the power-conversion efficiency of organic solar cells.Mohammed AzzouziJun YanThomas KirchartzKaikai LiuJinliang WangHongbin WuJenny NelsonAmerican Physical SocietyarticlePhysicsQC1-999ENPhysical Review X, Vol 8, Iss 3, p 031055 (2018)
institution	DOAJ
collection	DOAJ
language	EN
topic	Physics QC1-999
spellingShingle	Physics QC1-999 Mohammed Azzouzi Jun Yan Thomas Kirchartz Kaikai Liu Jinliang Wang Hongbin Wu Jenny Nelson Nonradiative Energy Losses in Bulk-Heterojunction Organic Photovoltaics
description	The performance of solar cells based on molecular electronic materials is limited by relatively high nonradiative voltage losses. The primary pathway for nonradiative recombination in organic donor-acceptor heterojunction devices is believed to be the decay of a charge-transfer (CT) excited state to the ground state via energy transfer to vibrational modes. Recently, nonradiative voltage losses have been related to properties of the charge-transfer state such as the Franck-Condon factor describing the overlap of the CT and ground-state vibrational states and, therefore, to the energy of the CT state. However, experimental data do not always follow the trends suggested by the simple model. Here, we extend this recombination model to include other factors that influence the nonradiative decay-rate constant, and therefore the open-circuit voltage, but have not yet been explored in detail. We use the extended model to understand the observed behavior of series of small molecules:fullerene blend devices, where open-circuit voltage appears insensitive to nonradiative loss. The trend could be explained only in terms of a microstructure-dependent CT-state oscillator strength, showing that parameters other than CT-state energy can control nonradiative recombination. We present design rules for improving open-circuit voltage via the control of material parameters and propose a realistic limit to the power-conversion efficiency of organic solar cells.
format	article
author	Mohammed Azzouzi Jun Yan Thomas Kirchartz Kaikai Liu Jinliang Wang Hongbin Wu Jenny Nelson
author_facet	Mohammed Azzouzi Jun Yan Thomas Kirchartz Kaikai Liu Jinliang Wang Hongbin Wu Jenny Nelson
author_sort	Mohammed Azzouzi
title	Nonradiative Energy Losses in Bulk-Heterojunction Organic Photovoltaics
title_short	Nonradiative Energy Losses in Bulk-Heterojunction Organic Photovoltaics
title_full	Nonradiative Energy Losses in Bulk-Heterojunction Organic Photovoltaics
title_fullStr	Nonradiative Energy Losses in Bulk-Heterojunction Organic Photovoltaics
title_full_unstemmed	Nonradiative Energy Losses in Bulk-Heterojunction Organic Photovoltaics
title_sort	nonradiative energy losses in bulk-heterojunction organic photovoltaics
publisher	American Physical Society
publishDate	2018
url	https://doaj.org/article/cb8ca1d8600d4e44858d19bba5e91a4e
work_keys_str_mv	AT mohammedazzouzi nonradiativeenergylossesinbulkheterojunctionorganicphotovoltaics AT junyan nonradiativeenergylossesinbulkheterojunctionorganicphotovoltaics AT thomaskirchartz nonradiativeenergylossesinbulkheterojunctionorganicphotovoltaics AT kaikailiu nonradiativeenergylossesinbulkheterojunctionorganicphotovoltaics AT jinliangwang nonradiativeenergylossesinbulkheterojunctionorganicphotovoltaics AT hongbinwu nonradiativeenergylossesinbulkheterojunctionorganicphotovoltaics AT jennynelson nonradiativeenergylossesinbulkheterojunctionorganicphotovoltaics
_version_	1718395190720331776

Nonradiative Energy Losses in Bulk-Heterojunction Organic Photovoltaics

Ejemplares similares