Optical and Charge Transport Properties of an Ambipolar Quinoidal Oligothiophene Derivative

Abstract

We report on the charge transport and absorption properties of a low bandgap quinoidal oligothiophene derivative [QQT(CN)4]. Organic field-effect transistors based on as-prepared QQT(CN)4 thin films show an ambipolar p-type dominant behavior and can be converted to n-type by thermal annealing at 100°C for 30 minutes. Absorption spectra and atomic force microscopy measurements carried out in both neat films and polymer blends provide new important insights into the role of the degree of aggregation and the intermolecular interactions on the semiconducting and photophysical properties of this organic electronic material.

Keywords:

• Quinoidal oligothiophene
• ambipolar organic transistor
• majority carrier type conversion
• degree of aggregation
• optical properties

Acknowledgment

JCR and LM would like to acknowledge funding from the STAR program. JCR also gratefully acknowledges funding from the Ewha internal research grant program. The research leading to these results has also received funding from the Japanese Society for the Promotion of Science via a JSPS KAKENHI grant (No.22350084).