초록 |
Four kinds of dimeric acceptor were synthesized and developed to control the regioregularity of thienoquinoline (TQO) and thienoisoquinoline (TIQO). In biTQO(P) or biTIQO(P), the phenyl unit of TQO or TIQO was connected to each other to form dimers. In contrast, thiophen unit of TQO or TIQO was linked to each other to afford biTQO(T) or biTIQO(T). We synthesized regioregular copolymers, PBDT-biTQO(P), PBDT-biTQO(T), PBDT-biTIQO(P) and PBDT-biTIQO(T), that were based on dimeric acceptors as an electron-accepting component and BDT as an electron-donating component to investigate their photovoltaic properties. The regioregular polymers show wide optical bandgap (2.10 eV). All copolymers exhibited better crystallinity with crystal coherence length than those of copolymers based on monomeric acceptors (TQO or TIQO). The device of PBDT-biTIQO(P):IT-4F was achieved the best PCE of 8.35 % with enhanced short-circuit current and fill factor. |