| 초록 |
Electron acceptors with fluorine lead to low HOMO and LUMO energy level and charge recombination of conjugated polymers because of the strong electron affinity. However, the polymers containing fluorine need to be enhanced solubility. Alkyl groups increase solubility of polymers and make an uniform mixture between polymer and PCBM. In this study, using 4,7-Di(thiophen-2-yl)-2,1,3-benzothiadiazole (BT) as an acceptor, polymers were synthesized by Stille coupling reaction. Then, two fluorine atoms at the 5,6-positions of BT were used for low HOMO energy level. Also, alkyl groups at the 4-positions of the flanking thienyl units were introduced to increase solubility. The synthesized copolymers were characterized by 1H-NMR, GPC, UV-visible spectroscopy and cyclic voltammogram. |
