Herein, we report the synthesis, characterization, and their photovoltaic and field-effect properties of two dialkoxyl-substituted naphthodithieno[3,2-b]thiophene (NDTT)-based copolymers, namely P1 and P2. The NDTT-based copolymers exhibit broad absorption profiles throughout the visible spectrum up to ca. 800 nm. The copolymers have HOMO/LUMO energy levels of ca. -5.14 eV/-3.52 eV. The dialkoxyl-substituted NDTT units endow the copolymers with enhanced solution processability, and crystalline stacking thin films with small π-π distances of down to 3.59 Å. Polymer-fullerene bulk heterojunction solar cells that fabricated from a blend of P2/PC71BM using diiodooctane as a solvent additive, afforded the highest power conversion efficiency of 3.54%. Solution-processed polymer field-effect transistors based on P1 with bottom-gate bottom-contact geometry exhibited promising hole mobilities of 0.070 cm2 V-1 s-1.
Scopus Subject Areas
- Chemical Engineering(all)
- Process Chemistry and Technology
- Charge transport properties
- Photovoltaic properties