Electrical and photoresponse properties of printed thin-film transistors based on poly(9,9-dioctylfluorene-co -bithiophene) sorted large-diameter semiconducting carbon nanotubes
Qian L., Xu W., Fan X., Wang C., Zhang J., Zhao J., Cui Z.
In this work, a simple and effective method has been developed to selectively separate large-diameter semiconducting-SWCNTs (sc-SWCNTs) from commercial arc discharge SWCNTs using (9,9-dioctylfluorene-co-bithiophene) (F8T2). The role of solvents in the separation and dispersion processes was studied. It has been proved that sc-SWCNTs mixed in arc discharge SWCNTs can be selectively sorted by F8T2 in toluene, xylene, or m-xylene with the aid of sonication and centrifugation, and the molecular dynamic simulation also agrees with the experiment results. The resulted sc-SWCNTs dispersion solution was used as a printable ink to print thin-film transistors (TFTs) via an aerosol jet printer. The printed TFTs showed good uniformity and electrical properties with on current up to 10-3 A, effective mobility up to 42.1 cm2 V-1 s-1 (±1.2 cm2 V-1s -1), and on/off ratio of ∼107 after only four cycles of repeated printing. In addition, all of the printed devices exhibited rapid photocurrent response to light irradiation. © 2013 American Chemical Society.