Synthesis and electrical properties of novel oligomer semiconductors for organic field-effect transistors (OFETs): Asymmetrically end-capped acene-heteroacene conjugated oligomers

Abstract

Noble small molecules composed of an aromatic phenylene-trithiophene and naphthalene-trithiophene conjugated core were synthesized and examined for their property in p-type OFET devices. The phenylene and naphthalene moieties were combined with a trithiophene to introduce torsional structures into the conjugated core and improve the solubility compared with the solubility of the quaterthiophene core containing molecule. Although phenylene-trithiophene and naphthalene-trithiophene containing molecules showed lower mobilities (2.9 x 10(-3) and 1.04 x 10(-2) cm(2)/V, respectively) than quaterthiophene containing molecule (3.21 x 10(-2) cm(2)/V), they showed more film uniformity caused by improved solubility. The thermal stability, photochemical properties, and morphological characteristics were investigated using TGA, DSC, cyclic voltammetry, and XRD techniques. (C) 2014 Elsevier Ltd. All rights reserved.