Synthesis and photovoltaic performances of benzo[1, 2‐b:4, 5‐b']dithiophene‐alt‐2, 3‐diphenylquinoxaline copolymers pending functional groups in phenyl rings. Issue 5 (4th December 2012)

• Record Type: Journal Article
• Authors: Tan, Hua; Deng, Xianping; Yu, Junting; Chen, Jianhua; Nie, Kaixuan; Huang, Ying; Liu, Yu; Wang, Yafei; Zhu, Meixiang; Zhu, Weiguo
• Is Part Of: Journal of polymer science. Volume 51:Issue 5(2013:Mar.)
• Page Start: 1051
• Page End: 1057
• Publication Date: 2012-12-04
• Subjects: 547
• DOI: 10.1002/pola.26477
• Languages: English
• ISSNs: 0887-624X

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>Two donor/acceptor (D/A)‐based benzo[1, 2‐b:4, 5‐b′]dithiophene‐<italic>alt</italic>‐2, 3‐biphenyl quinoxaline copolymers of <bold>P</bold>1 and <bold>P</bold>2 were synthesized pending different functional groups (thiophene or triphenylamine) in the 4‐positions of phenyl rings. Their thermal, photophysical, electrochemical, and photovoltaic properties, as well as morphology of their blending films were investigated. The poly(4, 8‐bis((2‐ethyl‐hexyl)oxy)benzo[1, 2‐b:4, 5‐b'] dithiophene)‐<italic>alt</italic>‐(2, 3‐bis(4′‐bis(N, N‐bis(4‐(octyloxy) phenylamino)‐ 1, 1′‐biphen‐4‐yl)quinoxaline) (<bold>P</bold>2) exhibited better photovoltaic performance than poly(4, 8‐bis((2‐ethylhexyl)oxy)benzo[1, 2‐b:4, 5‐b'] dithiophene)‐<italic>alt</italic>‐(2, 3‐bis(4‐(5‐octylthiophen‐2‐yl)phenyl)quinoxaline) (<bold>P</bold>1) in the bulk‐heterojunction polymer solar cells with a configuration of ITO/PEDOT:PSS/polymers: [6, 6]‐phenyl‐C<sub>71</sub>‐butyric acid methyl ester (PC<sub>71</sub>BM)/LiF/Al. A power conversion efficiency of 3.43%, an open‐circuit voltage of 0.80 V, and a short‐circuit current of 9.20 mA cm<sup>−2</sup> were achieved in the <bold>P</bold>2‐based cell under the illumination of AM 1.5, 100 mW cm<sup>−2</sup>. Importantly, this power conversion efficiency level is 2.29 times higher than that in the <bold>P</bold>1‐based cell. Our work indicated that incorporating triphenylamine pendant in the D/A‐based polymers can greatly improved the photovoltaic properties for its resulting polymers.</p> </abstract>