A stability study of polymer solar cells using conjugated polymers with different donor or acceptor side chain patterns. Issue 42 (12th October 2016)

• Record Type: Journal Article
• Authors: Heckler, Ilona M.; Kesters, Jurgen; Defour, Maxime; Penxten, Huguette; Van Mele, Bruno; Maes, Wouter; Bundgaard, Eva
• Is Part Of: Journal of materials chemistry. Volume 4:Issue 42(2016)
• Page Start: 16677
• Page End: 16689
• Publication Date: 2016-10-12
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c6ta07244e
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : The position and nature of side chains in the donor–acceptor copolymer were investigated in terms of stability in polymer solar cells. Abstract : Improvement of the power conversion efficiency and long term stability remains to be of crucial importance for the further development of polymer solar cells (PSCs). Herein, a donor–acceptor copolymer based on 4, 8-di(thiophene-2′-yl)benzo[1, 2- b :4, 5- b ′]dithiophene (DTBDT) and 4, 7-di(thiophene-2′-yl)benzo[ c ][1, 2, 5]thiadiazole (DTBT), specifically selected because of its suitability for roll-coating in the ambient environment, is investigated in terms of operational stability via partial exchange (5 or 10%) of the alkyl side chain on either the donor or the acceptor monomer with a 2-hydroxyethyl or 2-phenylethyl group. It is shown that the exchange of the hexyl chain on the DTBT moiety has a negative impact on the stability of the polymer as well as on the performance of the resulting PSCs. On the other hand, partial exchange of the 2-hexyldecyl side chain of the BDT unit by a 2-hydroxyethyl group results in an improved photochemical stability of the polymer film and a higher efficiency of 5.6% for the spin-coated PSC. The stability of roll-coated devices also slightly increases with the incorporation of 10% of either the 2-hydroxyethyl or 2-phenylethyl side chain.