P-type doped ambipolar polymer transistors by direct charge transfer from a cationic organic dye Pyronin B ferric chloride

Abstract

We report a facile way to improve organic field effect transistor (OFET) performance based on low concentration doping of diketopyrrolopyrrole-thieno[3,2-bIthiophene (DPPT-TT) solution by an organic cationic dye, Pyronin B (PyB). DPPT-TT OFETs show significantly high field effect mobilities (up to 3.5 cm(2)v(-1) s(-1)) by optimizing the doping ratio and solvent selection. The devices also exhibit better on! off ratio by suppression of n-channel characteristics. Ultraviolet photoelectron spectroscopy and UV vis absorption spectra revealed efficient p-type doping in PyB doped DPPT-TT films, which was confirmed by the Fermi level shifting toward the highest occupied molecular orbital and red shift of the absorption spectrum. (C) 2016 Elsevier B.V. All rights reserved.