| 摘要： |
In order to search for new wide band gap materials, vertical benzodithiophene (BDT) is designed as an electron donating unit to construct D-A type conjugated polymers. Two polymers PVB1 and PVB2 were synthesized by the Stille coupling reaction with benzothiadiazole (BT) and thieno[3,4-c]pyrrole-4,6-dione (TPD) as the accepting moieties, respectively. These polymers show wide optical band gaps of over 2.0 eV and low HOMO energy levels of below -5.5 eV. Polymer solar cell (PSC) devices were fabricated using the above polymers as donors and fullerene derivatives as acceptors. PSCs based on PVB1 and PC71BM showed a power conversion efficiency (PCE) of 2.84% with a V-oc of 1.00 V, a J(sc) of 6.80 mA cm(-2) and a FF of 0.42. And PSCs based on PVB2 and PC71BM showed a PCE of 2.05% with a V-oc of 1.09 V, a J(sc) of 5.33 mA cm(-2) and a FF of 0.35. Both polymers showed a high V-oc of over 1.0 V, which should be attributed to the deep-lying HOMO levels of the polymers. They would be potential candidates as wide band gap components to construct tandem solar cells. |
