Charge transport properties of Butterfly-like shape fused-thiophene based liquid crystalline organic semiconductors

Abstract

In this study, mesomorphous butterfly-like shape molecules based on cyclopentadithiophen-4-one and benzodithiophene-4,8-dione core moieties were synthesized. These butterfly-like shape molecules spontaneously self-organize into columnar hexagonal mesophase. The charge carrier mobility was measured by time-of-flight transient photocurrent technique in the mesophases. They display hole-transport performances with positive charge mobility in the 10-3 cm-2 V-1 s-1 range, consistent with the high degree of ordering and stability of the columnar superstructures. One mesogen in particular with benzodithiophen-4,8-dione core (BDTD) shows outstanding ambipolar charge carrier transport with both high electron (μe = 6.6×10-3 cm-2 V-1 s-1) and hole (μh = 4.5×10-3 cm-2 V-1 s-1) mobility values.