| 초록 |
A series of novel 5,8-dibromo-6,7-difluoro-2,3-dihexylquinoxaline(DFQx) based alternating copolymers were synthesized using a direct arylation, Stille or Suzuki polymerization reaction. These polymers were made from bis(trimethyltin)-4,8-bis(2-octyloxy)benzo[1,2-b:3,4-b']dithiophene, 4,4-bis(2-ethylhexyl)-4H-cyclopenta[1,2-b:5,4-b']dithiophene, 4,4-dioctyl-4H-silolo[3,2-b:4,5-b']dithiophene, 2,7-dibromo-9,9-bis(2-ethylhexyl)-9H-fluorene or 2,7-dibromo-9-(heptadecan-9-yl)-9H-carbazole as an donor. A highest occupied molecular orbital (HOMO) energy level was exhibited in the range of -5.24 eV ~ -5.80 eV. All the polymers show narrow band gaps below 2.2eV. Thermogravimetry Analysis(TGA) of polymerizations were measured to be 410℃, 350℃, 316℃, 313℃ and 386℃. The thin film based on copolymers including cyclopentadithiophene derivative was able harvest a broad solar spectrum covering the range from 350 to 700 nm. |
