title: Design and photovoltaic characterization of dialkylthio benzo[1,2-b:4,5-b']dithiophene polymers with different accepting units.
abstract: Three dialkylthio benzo[1,2-b:4,5-b']dithiophene (S-BDT) based polymers have been developed using different accepting units to tune their bandgaps. The polymer:PC71BM solar cells achieved the highest power conversion efficiency (PCE) of 4.51% without any post-treatment (such as annealing and solvent additive) in conventional single-cell devices. Joint photophysical, electrical and computational studies on the polymer based solar cells revealed the considerable impact of molecular planarity on polymer design. The polymer:PC71BM devices processed with 1,8-diiodooctane for improving their morphology afforded an improved PCE value of 5.63%, with a Voc of 0.83, a Jsc of 10.24 mA cm(-2) and a FF of 66.3%.
authors.affiliation: Key Laboratory of Soft Chemistry and Functional Materials, Ministry of Education, Nanjing University of Science and Technology, Nanjing 210094, China. whtang@mail.njust.edu.cn.
authors.forename: Guidong
authors.initials: G
authors.lastname: Ge
authors.forename: Jinan
authors.initials: J
authors.lastname: Gu
authors.forename: Jiangsheng
authors.initials: J
authors.lastname: Yu
authors.forename: Enwei
authors.initials: E
authors.lastname: Zhu
authors.forename: Jiefeng
authors.initials: J
authors.lastname: Hai
authors.forename: Linyi
authors.initials: L
authors.lastname: Bian
authors.forename: Fujun
authors.initials: F
authors.lastname: Zhang
authors.forename: Zhongsheng
authors.initials: Z
authors.lastname: Xu
authors.forename: Wanli
authors.initials: W
authors.lastname: Ma
authors.forename: Weihua
authors.initials: W
authors.lastname: Tang