High performance thin film transistors based on regioregular poly(3-dodecylthiophene)-sorted large diameter semiconducting single-walled carbon nanotubes

Abstract

In this work, a simple and rapid method to selectively sort semiconducting-SWCNTs (sc-SWCNTs) with large diameters using regioregular poly(3-dodecylthiophene) (rr-P3DDT) is presented. The absorption spectra and Raman spectra demonstrated that metallic species of arc discharge SWCNTs were effectively removed after interaction with rr-P3DDT in toluene with the aid of sonication and centrifugation. The sorted sc-SWCNT inks have been directly used to fabricate thin film transistors (TFTs) by dip-coating, drop-casting and inkjet printing. TFTs with an effective mobility of ∼34 cm² V⁻¹ s⁻¹ and on–off ratios of ∼10⁷ have been achieved by dip coating and drop casting the ink on SiO₂/Si substrates with pre-patterned interdigitated gold electrode arrays. The printed devices also showed excellent electrical properties with a mobility of up to 6.6 cm² V⁻¹ s⁻¹ and on–off ratios of up to 10⁵. Printed inverters based on the TFTs have been constructed on glass substrates, showing a maximum voltage gain of 112 at a V_dd of −5 V. This work paves the way for making printable logic circuits for real applications.