Solution-processed n-type organic field-effect transistors based on electronegative oligothiophenes having fully oxo-substituted terthiophenes

An electronegative π-conjugated system comprising difluorodioxocyclopentene-annelated thiophene and dialkyl-substituted naphtho[2,3-c]thiophene-4,9-dione has been synthesized as a candidate material for fabricating solution-processable n-type organic field-effect transistors (OFETs). The photophysical and electrochemical properties of the abovementioned compounds were investigated, and their frontier-orbital energy levels were estimated from the experimental and calculated data. OFETs fabricated by spin coating revealed good n-type characteristics with electron mobilities up to 0.016 cm2 V−1 s−1. Further, the performance of the fabricated OFETs were investigated under biased or air-exposure conditions.