Design and synthesis of the polymers based on alkylthiophenyl side chains and variant acceptor moieties for polymer solar cells. Issue 97 (5th October 2016)

• Record Type: Journal Article
• Authors: Liu, Hailu; Zhang, Zhiquan; Zeng, Zhaokui; Zhao, Bin; Tan, Songting
• Is Part Of: RSC advances. Volume 6:Issue 97(2016)
• Page Start: 95306
• Page End: 95313
• Publication Date: 2016-10-05
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c6ra19030h
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : Three new BDT-based polymers with alkylthiophenyl side chains and the relationship between the acceptor structure and the photovoltaic performance. Abstract : Three donor–acceptor (D–A) copolymersPSB-DFBT, PSB-DTDFBT andPSB-FTT, consisting of alkylthiophenyl group-substituted benzo[1, 2- b :4, 5- b ′]dithiophene (SB) as the donor moieties and different electron-deficient units as the acceptor moieties, have been designed and synthesized. The effects of the variant acceptor moieties on the photophysical, electrochemical and photovoltaic properties of the polymers were investigated. Compared with the polymersPSB-DFBT andPSB-DTDFBT with 5, 6-difluorobenzo[ c ][1, 2, 5]thiadiazole as the acceptor moieties, the polymerPSB-FTT with 2-ethylhexyl-3-fluorothieno[3, 4- b ]thiophene-2-carboxylate (FTT) as the acceptor moieties shows smaller band gap, stronger light harvesting capacity, better appropriate microphase separation with (7, 7)-phenyl-C71 -butyric acid methyl ester (PC71 BM), smaller domain size, more effective exciton dissociation and higher hole mobility. Therefore, thePSB-FTT -based bulk heterojunction solar cell exhibits a higher power conversion efficiency of 4.45% than that of thePSB-DFBT - (1.88%) andPSB-DTDFBT -based devices (0.48%).