title: Medium Bandgap Conjugated Polymer for High Performance Polymer Solar Cells Exceeding 9% Power Conversion Efficiency.
abstract: Two medium-bandgap polymers composed of benzo[1,2-b:4,5-b']dithiohpene and 2,1,3-benzothiadiazole with 6-octyl-thieno[3,2-b]thiophene as a π-bridge unit are synthesized and their photovoltaic properties are analyzed. The two polymers have deep highest occupied molecular orbital energy levels, high crystallinity, optimal bulk-heterojunction morphology, and efficient charge transport, resulting in a power conversion efficiency of as high as 9.44% for a single-junction polymer solar-cell device.
authors.affiliation: Department of Materials Science and Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-744, South Korea.
authors.forename: Jae Woong
authors.initials: JW
authors.lastname: Jung
authors.affiliation: Department of Polymer Science and Engineering, University of Massachusetts, Amherst, MA, 01003, USA.
authors.forename: Feng
authors.initials: F
authors.lastname: Liu
authors.affiliation: Department of Polymer Science and Engineering, University of Massachusetts, Amherst, MA, 01003, USA.
authors.forename: Thomas P
authors.initials: TP
authors.lastname: Russell
authors.affiliation: Department of Materials Science and Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-744, South Korea.
authors.forename: Won Ho
authors.initials: WH
authors.lastname: Jo
keywords: conjugated polymers; polymer solar cells; power conversion efficiency