| 초록 |
A series of acceptor-donor-acceptor (A-D-A) type oligomer based on benzothiadiazole (BT) and a series of central unit such as carbazole (Cz), Cz-BT; CzT-BT and CzBT-DP, and phenothiazine, PTBT are synthesized by the Suzuki coupling reaction to investigate the effect of combination between strong electron donor and strong electron acceptor properties of conjugated oligomer. In Cz-BT, CzT-BT, CzBT-DP and PTBT, thiophene ring was added as a -bridge to extend the effective of conjugation length. Addition of thiophene affect the HOMO level which make Cz-BT, CzT-BT, CzBT-DP and PTBT has high lying HOMO level.Maximum power conversion efficiency (PCE) of the OSCs based on small molecules is showed up to 1.58%, the Voc, Jsc, and FF were 1.04 ~ 1.06 V, 2.52 ~ 3.46 mA/cm2, and 37.0 ~ 47.3% from the devices based Cz-BT. Among the devices, the best PCE of the device showed at the Cz-BT:PC71BM ratio of a 3:3. |
