文摘
Dicyanomethylene-substituted quinoidal dithieno[2,3-d;2鈥?3鈥?d鈥瞉benzo[1,2-b;4,5-b鈥瞉dithiophene compounds (QDTBDTs) with alkyl chains branched at different positions were synthesized. Thin-film transistor characteristics showed that the type of charge carriers in QDTBDTs could be tuned by changing the branching position of the alkyl chains. QDTBDT-2C exhibited n-channel behavior, and the observed electron mobility was 0.57 cm2 V鈥? s鈥? without post-treatment, one of the highest values reported for spin-coated thin-film transistors with no annealing under ambient conditions. QDTBDT-4C-based transistors displayed electron-dominated ambipolar transport behavior, with electron mobilities reaching 0.2 cm2 V鈥? s鈥? and hole mobilities in the range of 10鈥?鈥?0鈥? cm2 V鈥? s鈥?. QDTBDT-3C showed solution-concentration-dependent carrier transport characteristics, exhibiting n-type behavior at low solution concentrations and ambipolar performance at high solution concentrations with an electron mobility of 0.22 cm2 V鈥? s鈥? and a hole mobility of 0.034 cm2 V鈥? s鈥?. CMOS-like inverters fabricated from QDTBDT-2C displayed high gain and high noise margins.