| 초록 |
Three new quinoxaline polymers were prepared with the aim of exploring TFQ-based polymers on fullerene-free organic solar cells (OSCs). The electron-rich benzo[1,2-b:4,5-bʹ]dithiophene unit contains three different substituents, namely BDTO, BDTT, and BDTS. These were polymerized with electron deficient Dibromo TFQ to afford the polymers P(BDTO-TFQ), P(BDTT-TFQ), and P(BDTS-TFQ). The estimated band-gaps and the highest occupied molecular orbital levels were 1.88, 1.86, and 1.94 eV, –5.35, –5.44, and –5.58 eV, respectively. The OSCs made with a blend of polymer and ITIC gave the maximum power-conversion efficiencies of 3.49, 7.06, and 0.75%, respectively. Overall, the substituents attached at the 4- and 8-positions of the BDT unit of the TFQ-based polymers were found to exhibit greatly altered properties, such as their absorption, energy levels, and crystallinity. This resulted in dissimilar photovoltaic performance for the resulting polymers. |
