| 초록 |
Conjugated polymer/fullerene bulk heterojunction (BHJ) solar cells have received increased attention because of their promising energy conversion efciencies, solution processability, and low cost. Poly(fluorene)s have been used as active materials, but their efficiency has been quite low due to limited absorption of short wavelength only and large band gap. To achieve a device with a high light harvesting ability as well as a high open-circuit voltage, one feasible approach is to design alternating donor-acceptor copolymers where the fluorene unit may provide a deeper HOMO level and the electron donor unit is used to tune the electronic band gap of the polymers. In this study, the donor was a polyfluorene derivative, which is composed of electron-withdrawing cyano-substituent end groups. Poly(fluorene) copolymers were synthesized by Suzuki Coupling method. The optical and physical properties of materials were characterized and the organic photovoltaic cells were fabricated. |
