Electropolymerizations and electrochromic performances of tetrathiafulvalene-σ-thiophenes

Three tetrathiafulvalene (TTF)-functionalized thiophene (Th) monomers with different σ bridges were synthesized. The UV–Vis spectra and CV implied that the weak intramolecular charge transfer effects existed in these monomers. They could be electropolymerized into the polythiophenes with TTF unit as pendant group during the CV and CA processes, while the electropolymerization of non-TTF-substituted thiophenes failed under the same conditions. The electropolymerized P (TTF-σ-Th) exhibited good electrochromic performances, especially in P (TTF-Th-3), due to the thiophene backbone activated by the TTF group. Novel Tetrathiafulvalene-σ-Thiophenes monomers were successfully electropolymerized with good electrochromic performance due to the activation effect of TTF pendent.