Electrical and Photoresponse Properties of Printed Thin-Film Transistors Based on Poly(9,9-dioctylfluorene-<i>co</i>-bithiophene) Sorted Large-Diameter Semiconducting Carbon Nanotubes

Abstract

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 cm 2 V –1 s –1 (±1.2 cm 2 V –1 s –1 ), and on/off ratio of ∼10 7 after only four cycles of repeated printing. In addition, all of the printed devices exhibited rapid photocurrent response to light irradiation.