Effect of thionation on the performance of PNDIT2-based polymer solar cells

Kira Rundel, Young Hun Shin, Anthony S.R. Chesman, Amelia C.Y. Liu, Adam Welford, Lars Thomsen, Michael Sommer, Christopher R. McNeill

Research output: Contribution to journalArticleResearchpeer-review

Abstract

All-polymer solar cells have gained attention in recent years with a solar cell performance of over 11% power conversion efficiency (PCE) recently demonstrated. The n-type polymer PNDIT2, also known as N2200 or P(NDI2OD-T2), has been extensively used for both photovoltaic and field-effect transistor applications. When paired with donor materials that have appropriately aligned energy levels, PNDIT2 exhibited device efficiencies over 10% PCE, and organic field-effect transistors fabricated with PNDIT2 exhibited mobilities over 1 cm 2 /V s. Thionation of the naphthalene diimide (NDI) moiety, which is the substitution of imide oxygen with sulfur atoms, has been shown to improve the field-effect transistor performance of NDI-based small molecules. By applying this strategy to PNDIT2, we explored the effect that thionation, in a 2S-trans configuration, has on the performance of all-polymer solar cells fabricated with the donor polymer PTB7-Th. Solar cells were fabricated with the original polymer, PNDIT2, as a reference, and an optimized efficiency of 4.85% was achieved. As samples with 100% conversion to 2S-trans configuration could not be produced because of synthetic limitations, batches with increasing ratios of 1S to 2S-trans thionation (15:85, 7:93, and 5:95) were studied. Devices with thionated PNDIT2 exhibited a systematic lowering of photovoltaic parameters with increasing thionation, resulting in device efficiencies of just 0.84, 0.62, and 0.42% PCE, respectively. The lower performance of the thionated blends is attributed to poor π-πstacking order in the thionated PNDIT2 phase, resulting in lower electron mobilities and finer phase separation. Evidence in support of this conclusion is provided by grazing incidence wide-angle X-ray scattering, transmission electron microscopy, photoluminescence quenching, transient photocurrent analysis, and space-charge-limited current measurements.

Original languageEnglish
Pages (from-to)12062−12072
Number of pages11
JournalJournal of Physical Chemistry C
Volume123
Issue number19
DOIs
Publication statusPublished - 16 May 2019

Cite this

Rundel, Kira ; Shin, Young Hun ; Chesman, Anthony S.R. ; Liu, Amelia C.Y. ; Welford, Adam ; Thomsen, Lars ; Sommer, Michael ; McNeill, Christopher R. / Effect of thionation on the performance of PNDIT2-based polymer solar cells. In: Journal of Physical Chemistry C. 2019 ; Vol. 123, No. 19. pp. 12062−12072.
@article{59ca6fa8954344b6ab2c1e699f4e6ef5,
title = "Effect of thionation on the performance of PNDIT2-based polymer solar cells",
abstract = "All-polymer solar cells have gained attention in recent years with a solar cell performance of over 11{\%} power conversion efficiency (PCE) recently demonstrated. The n-type polymer PNDIT2, also known as N2200 or P(NDI2OD-T2), has been extensively used for both photovoltaic and field-effect transistor applications. When paired with donor materials that have appropriately aligned energy levels, PNDIT2 exhibited device efficiencies over 10{\%} PCE, and organic field-effect transistors fabricated with PNDIT2 exhibited mobilities over 1 cm 2 /V s. Thionation of the naphthalene diimide (NDI) moiety, which is the substitution of imide oxygen with sulfur atoms, has been shown to improve the field-effect transistor performance of NDI-based small molecules. By applying this strategy to PNDIT2, we explored the effect that thionation, in a 2S-trans configuration, has on the performance of all-polymer solar cells fabricated with the donor polymer PTB7-Th. Solar cells were fabricated with the original polymer, PNDIT2, as a reference, and an optimized efficiency of 4.85{\%} was achieved. As samples with 100{\%} conversion to 2S-trans configuration could not be produced because of synthetic limitations, batches with increasing ratios of 1S to 2S-trans thionation (15:85, 7:93, and 5:95) were studied. Devices with thionated PNDIT2 exhibited a systematic lowering of photovoltaic parameters with increasing thionation, resulting in device efficiencies of just 0.84, 0.62, and 0.42{\%} PCE, respectively. The lower performance of the thionated blends is attributed to poor π-πstacking order in the thionated PNDIT2 phase, resulting in lower electron mobilities and finer phase separation. Evidence in support of this conclusion is provided by grazing incidence wide-angle X-ray scattering, transmission electron microscopy, photoluminescence quenching, transient photocurrent analysis, and space-charge-limited current measurements.",
author = "Kira Rundel and Shin, {Young Hun} and Chesman, {Anthony S.R.} and Liu, {Amelia C.Y.} and Adam Welford and Lars Thomsen and Michael Sommer and McNeill, {Christopher R.}",
year = "2019",
month = "5",
day = "16",
doi = "10.1021/acs.jpcc.8b11935",
language = "English",
volume = "123",
pages = "12062−12072",
journal = "Journal of Physical Chemistry C",
issn = "1932-7447",
publisher = "American Chemical Society",
number = "19",

}

Rundel, K, Shin, YH, Chesman, ASR, Liu, ACY, Welford, A, Thomsen, L, Sommer, M & McNeill, CR 2019, 'Effect of thionation on the performance of PNDIT2-based polymer solar cells', Journal of Physical Chemistry C, vol. 123, no. 19, pp. 12062−12072. https://doi.org/10.1021/acs.jpcc.8b11935

Effect of thionation on the performance of PNDIT2-based polymer solar cells. / Rundel, Kira; Shin, Young Hun; Chesman, Anthony S.R.; Liu, Amelia C.Y.; Welford, Adam; Thomsen, Lars; Sommer, Michael; McNeill, Christopher R.

In: Journal of Physical Chemistry C, Vol. 123, No. 19, 16.05.2019, p. 12062−12072.

Research output: Contribution to journalArticleResearchpeer-review

TY - JOUR

T1 - Effect of thionation on the performance of PNDIT2-based polymer solar cells

AU - Rundel, Kira

AU - Shin, Young Hun

AU - Chesman, Anthony S.R.

AU - Liu, Amelia C.Y.

AU - Welford, Adam

AU - Thomsen, Lars

AU - Sommer, Michael

AU - McNeill, Christopher R.

PY - 2019/5/16

Y1 - 2019/5/16

N2 - All-polymer solar cells have gained attention in recent years with a solar cell performance of over 11% power conversion efficiency (PCE) recently demonstrated. The n-type polymer PNDIT2, also known as N2200 or P(NDI2OD-T2), has been extensively used for both photovoltaic and field-effect transistor applications. When paired with donor materials that have appropriately aligned energy levels, PNDIT2 exhibited device efficiencies over 10% PCE, and organic field-effect transistors fabricated with PNDIT2 exhibited mobilities over 1 cm 2 /V s. Thionation of the naphthalene diimide (NDI) moiety, which is the substitution of imide oxygen with sulfur atoms, has been shown to improve the field-effect transistor performance of NDI-based small molecules. By applying this strategy to PNDIT2, we explored the effect that thionation, in a 2S-trans configuration, has on the performance of all-polymer solar cells fabricated with the donor polymer PTB7-Th. Solar cells were fabricated with the original polymer, PNDIT2, as a reference, and an optimized efficiency of 4.85% was achieved. As samples with 100% conversion to 2S-trans configuration could not be produced because of synthetic limitations, batches with increasing ratios of 1S to 2S-trans thionation (15:85, 7:93, and 5:95) were studied. Devices with thionated PNDIT2 exhibited a systematic lowering of photovoltaic parameters with increasing thionation, resulting in device efficiencies of just 0.84, 0.62, and 0.42% PCE, respectively. The lower performance of the thionated blends is attributed to poor π-πstacking order in the thionated PNDIT2 phase, resulting in lower electron mobilities and finer phase separation. Evidence in support of this conclusion is provided by grazing incidence wide-angle X-ray scattering, transmission electron microscopy, photoluminescence quenching, transient photocurrent analysis, and space-charge-limited current measurements.

AB - All-polymer solar cells have gained attention in recent years with a solar cell performance of over 11% power conversion efficiency (PCE) recently demonstrated. The n-type polymer PNDIT2, also known as N2200 or P(NDI2OD-T2), has been extensively used for both photovoltaic and field-effect transistor applications. When paired with donor materials that have appropriately aligned energy levels, PNDIT2 exhibited device efficiencies over 10% PCE, and organic field-effect transistors fabricated with PNDIT2 exhibited mobilities over 1 cm 2 /V s. Thionation of the naphthalene diimide (NDI) moiety, which is the substitution of imide oxygen with sulfur atoms, has been shown to improve the field-effect transistor performance of NDI-based small molecules. By applying this strategy to PNDIT2, we explored the effect that thionation, in a 2S-trans configuration, has on the performance of all-polymer solar cells fabricated with the donor polymer PTB7-Th. Solar cells were fabricated with the original polymer, PNDIT2, as a reference, and an optimized efficiency of 4.85% was achieved. As samples with 100% conversion to 2S-trans configuration could not be produced because of synthetic limitations, batches with increasing ratios of 1S to 2S-trans thionation (15:85, 7:93, and 5:95) were studied. Devices with thionated PNDIT2 exhibited a systematic lowering of photovoltaic parameters with increasing thionation, resulting in device efficiencies of just 0.84, 0.62, and 0.42% PCE, respectively. The lower performance of the thionated blends is attributed to poor π-πstacking order in the thionated PNDIT2 phase, resulting in lower electron mobilities and finer phase separation. Evidence in support of this conclusion is provided by grazing incidence wide-angle X-ray scattering, transmission electron microscopy, photoluminescence quenching, transient photocurrent analysis, and space-charge-limited current measurements.

UR - http://www.scopus.com/inward/record.url?scp=85065794279&partnerID=8YFLogxK

U2 - 10.1021/acs.jpcc.8b11935

DO - 10.1021/acs.jpcc.8b11935

M3 - Article

VL - 123

SP - 12062−12072

JO - Journal of Physical Chemistry C

JF - Journal of Physical Chemistry C

SN - 1932-7447

IS - 19

ER -