Two alternating polymers based on two-dimensional conjugated benzo[1,2-b:4,5-b']difuran and fluorinated quinoxaline derivatives were synthesized. Their structures are poly{4,8-bis(2,3-(dioctyl)thiophen-5-yl)-benzo[1,2-b:4,5-b']difuran-alt-5,8-bis(thiophen-2-yl)-6-fluoro-2,3-bis(3-octyloxyphenyl) quinoxaline} (P1, mono F) and poly{4,8-bis(2,3-(dioctyl)thiophen-5-yl)-benzo[1,2-b:4,5-b']difuran-alt-5,8-bis(thiophen-2-yl)-6,7-difluoro-2,3-bis(3-octyloxyphenyl) quinoxaline} (P2, double F). UVvis absorption measurements show that the difluorinated polymer P2 exists a higher absorption in comparison with the mono fluorinated polymer P1 either in the solution or in the film. Electrochemical measurements confirm that the polymer P2 displays low energy levels (-5.30 eV and -3.25 eV) of both highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) in comparison with those of P1 (-5.25 eV and -3.20 eV). Photovoltaic cells with conventional device configuration of ITO/PEDOT:PSS/polymer:PC71BM/PFN/Al were fabricated. The power conversion efficiency (PCE) of the optimized polymer solar cells (PSCs) based on P1 reaches 2.22% with a current density of 5.28 mA/cm(2). However, a high PCE of 4.44% with a high current density of 8.74 mA/cm2 was obtained for the double fluorinated polymer P2 based device. (C) 2015 Elsevier Ltd. All rights reserved.