Solar Energy Materials and Solar Cells, Vol.104, 45-52, 2012
A novel copolymer from benzodithiophene and alkylsulfanyl-bithiophene: Synthesis, characterization and application in polymer solar cells
We present the synthesis and characterization of a novel copolymer from benzodithiophene and alkylsulfanyl-bithiophene units, poly[4,8-bis(2-ethylhexyloxy)benzo[1,2-b:4,5-b']dithiophene-alt-4,4'-bis(octylsulfanyl)-2,2'-bithiophene] (PolyS). The structural, electrochemical and photophysical properties of PolyS were investigated by gel permeation chromatography (GPC), thermogravimetric analysis (TGA), NMR, UV-vis, photoluminescence (PL) spectroscopy and cyclic voltammetry (CV). PolyS was used to fabricate bulk-heterojunction polymer solar cells (PSCs) in combination with the PCBM and PCBM (electron acceptors). The device realized using PCBM shows a better current output due to the increased absorption of the blend film compared to the PolyS:PCBM one. The power conversion efficiency of the best PSC realized is 2.3% under 100 mW/cm(2) AM 1.5 G illumination. (C) 2012 Elsevier B.V. All rights reserved.