Synthesis of Two D-pi-A Polymers pi-Bridged by Different Blocks and Investigation of Their Photovoltaic Property

摘要

The synthesis, characterization, photophysical and photovoltaic properties of two 5,6-bis(octyloxy)benzo[c][1,2,5]thiadiazole-containing wide-band-gap donor and acceptor D-pi-A alternating conjugated polymers (HSD-a and HSD-b) have been reported. These two polymers absorb in the range of 300-700 nm with a band gap of about 1.88 and 1.97 eV. The HOMO energy levels were -5.44 eV for HSD-a and -5.63 eV for HSD-b. Polymer solar cells with HSD-b :PC71BM as the active layer demonstrated a power conversion efficiency (PCE) of 2.59% with a high V-oc of 0.93 V, a J(sc) of 7.3 mA/cm(2), and a comparable fill factor (FF) of 0.38 under simulated solar illumination of AM 1.5G (100 mW/cm(2)) without annealing. In addition, HSD-a :PC71BM blend-based solar cells exhibit a PCE of 2.15% with a comparable V-oc of 0.64 V, J(sc) of 8.75 mA/cm(-2), and FF of 0.40. (C) 2014 Wiley Periodicals, Inc.