Improved charge transport in fused-ring bridged hemi-isoindigo-based small molecules by incorporating a thiophene unit for solution-processed organic field-effect transistors

• Published in: Journal of materials chemistry. C, Materials for optical and electronic devices Materials for optical and electronic devices, 2020, Vol.8 (4), p.1398-1404
• Main Authors: Zhang, Guobing, Chen, Ruikun, Sun, Yue, Kang, Boseok, Sun, Mingxiang, Lu, Hongbo, Qiu, Longzhen, Cho, Kilwon, Ding, Yunsheng
• Format: Article
• Language: English
• Subjects: Bridge maintenance; Charge transport; Conjugation; Field effect transistors; Hole mobility; Morphology; Planar structures; Semiconductor devices; Semiconductor materials; Transistors
• ISSN: 2050-7526; 2050-7534
• DOI: 10.1039/C9TC05374C

Two acceptor–donor–acceptor small molecules based on a fused ring indacenodithieno[3,2- b ]thiophene ( IDTT ) as a donor, and hemi-isoindigo units, methyleneoxindole ( IDTT-MI ) and thienylmethyleneoxindole ( IDTT-T-MI ) as acceptors were synthesized and characterized for application in solution-processed organic field-effect transistors. The incorporation of a thiophene bridge which extended the conjugation of the backbone maintained highly co-planar structures, and also endowed the small molecule with ordered crystalline structures and interconnected morphology. Consequently, IDTT-T-MI -based organic field-effect transistors exhibited a highest hole mobility of 0.80 cm 2 V −1 s −1 , which was the highest mobility for solution-processed hemi-isoindigo-based organic semiconductor materials.