| 초록 |
There has been a few report on alternating copolymers containing strong acceptor unit with solubilizing group, although alternating copolymers with weak donor and strong acceptor units have recently been considered to be the most promising candidate for highly efficient polymer solar cells (PSCs), because fine-tuned energy levels of the copolymer may compensate negative effects of fullerene derivatives on the performance due to their relatively low LUMO levels of 4.3 eV. In PSCs, solubility of conjugated polymer is an important property because that affects polymerization, molecular weight, morphology, and device fabrication. In this study, we successfully synthesized thieno[3,4-d]thiazoles (TTz) with alkyl groups as a solubilizing group, and TTz was copolymerized with weak donors to form low bandgap polymers. The TTz with strong electron-withdrawing ability lowered the LUMO and HOMO energy levels of copolymers, which contributes to enhancement of the power conversion efficiency. |
