| dc.description.abstract | Two series of new quinoidals based on thioalkylated bithiopene
cores, DTDST and TSBT, have been developed for organic thin film
transistors (OTFTs).
For the first series, 3, 4-dithioalkylated thiophene was end capped
with thiophene to give DTDST core. Via the reaction of the latter with
dicyanomethane, tetradecylthio and hexylthio quinoidals, DTDSTQ-6 (1)
and DTDSTQ-14 (2) were developed. For comparison, tetradecylated
DTDRTQ-14 (3) was prepared. Currently, thioalkylated DTDSTQ-14 (2) exhibit the highest mobility up to 0.4 cm2/Vs. In contrast, non-thio
alkylated DTDRTQ-14 (3) exhibit lower mobility of 0.2 cm2/Vs. Perhaps
due to extensively intra- and inter- S…S molecular interaction, the former
with better conjugation, led to better molecular packing, and therefore
demonstrated higher performance.
For the second series, four thioalkylated bithiophenyl core, TSBT,
was prepared to improve the solubility of quinoidals. Tetradecylthio and
hexylthio quinoidals, TSBTQ-6 (4) and TSBTQ-14 (5) were developed.
Currently, TSBTQ-6 (4) exhibit mobility approach to 0.1 cm2/Vs.
All these new quinoidals exhibit pretty low LUMO (< -4.2 eV) and thus are potential air stable n-type materials. | en_US |