Investigation of the Effects of Non-Conjugated Co-Grafts on the Spectroelectrochemical and Photovoltaic Properties of Novel Conjugated Graft Copolymers Based on Poly(3-hexylthiophene)

Tomasz Jarosz; Karolina Gebka; Kinga Kepska; Mieczyslaw Lapkowski; Przemyslaw Ledwon; Pawel Nitschke; Agnieszka Stolarczyk

doi:10.3390/polym10101064

Investigation of the Effects of Non-Conjugated Co-Grafts on the Spectroelectrochemical and Photovoltaic Properties of Novel Conjugated Graft Copolymers Based on Poly(3-hexylthiophene)

Polymers (Basel). 2018 Sep 25;10(10):1064. doi: 10.3390/polym10101064.

Authors

Tomasz Jarosz^{1

2}, Karolina Gebka³, Kinga Kepska⁴, Mieczyslaw Lapkowski^{5

6}, Przemyslaw Ledwon⁷, Pawel Nitschke⁸, Agnieszka Stolarczyk⁹

Affiliations

¹ Department of Physical Chemistry and Technology of Polymers, Silesian University of Technology, 9 Strzody Street, 44-100 Gliwice, Poland. tomasz.jarosz@polsl.pl.
² Department of Inorganic Chemistry, Analytical Chemistry and Electrochemistry, Silesian University of Technology, 6 Krzywoustego Street, 44-100 Gliwice, Poland. tomasz.jarosz@polsl.pl.
³ Department of Physical Chemistry and Technology of Polymers, Silesian University of Technology, 9 Strzody Street, 44-100 Gliwice, Poland. karolina.gebka@polsl.pl.
⁴ Department of Physical Chemistry and Technology of Polymers, Silesian University of Technology, 9 Strzody Street, 44-100 Gliwice, Poland. kinga.kepska@polsl.pl.
⁵ Department of Physical Chemistry and Technology of Polymers, Silesian University of Technology, 9 Strzody Street, 44-100 Gliwice, Poland. mieczyslaw.lapkowski@polsl.pl.
⁶ Centre of Polymer and Carbon Materials Polish Academy of Sciences, 34 Curie-Sklodowskiej Street, 41-819 Zabrze, Poland. mieczyslaw.lapkowski@polsl.pl.
⁷ Department of Physical Chemistry and Technology of Polymers, Silesian University of Technology, 9 Strzody Street, 44-100 Gliwice, Poland. przemyslaw.ledwon@polsl.pl.
⁸ Centre of Polymer and Carbon Materials Polish Academy of Sciences, 34 Curie-Sklodowskiej Street, 41-819 Zabrze, Poland. pnitschke@cmpw-pan.edu.pl.
⁹ Department of Physical Chemistry and Technology of Polymers, Silesian University of Technology, 9 Strzody Street, 44-100 Gliwice, Poland. agnieszka.stolarczyk@polsl.pl.

Abstract

A new type of polysiloxane copolymers, with conjugated⁻regioregular poly(3-hexylthiophene) (P3HT) and non-conjugated-poly(ethylene glycol) (PEG)-grafts have been synthesised, and their properties have been studied alongside those of the parent conjugated polymer (P3HT). Spectroelectrochemical and conductometric analyses revealed an early rise of the conductance of the polymers. Once spectral changes begin taking place, the conductance is stable, implying a loss of mobility of charge carriers, even though standard doping/dedoping patterns are observed. Prototype bulk heterojunction solar cells have been fabricated, based on P3HT/[6,6]-Phenyl-C61-butyric acid methyl ester (PCBM), as well as by substituting P3HT for each of the copolymers. The prototype solar cells achieved PCEs of up to 2.11%. This is one of the highest reported power conversion efficiency (PCE) for devices based on P3HT with low average molecular weight M_n = 12 kDa. Strong correlation between the structure of the copolymer and its photovoltaic performance was found. Elongation of PEG copolymer chain and the use of methyl group instead of terminal hydroxyl groups significantly improved photovoltaic performance.

Keywords: functionalized conducting polymers; graft copolymers; poly(3-hexylthiophene); poly(ethylene glycol); solar cells.

Abstract

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