알킬 씨오펜 사이드 체인으로 치환된 폴리씨오펜 유도체의 유기반도체 소자 적용 및 평가: 용해도와 산화안정성

Abstract

Organic Field Effect Transistor with polymeric semiconductor as active layer, has been massively studied for this several decades, and various polythiophene derivatives have been attempted to this active layer of OFET. Here, we report the synthesis of polythiophene derivatives that contain decylthiophenyl side chains, using synthetic strategies that achieve high organic semiconductor field effect mobilities by enhancing the π-conjugation in the side chain conjugated system. With increased charge densities, we obtained high field effect mobilities, up to 0.050 cm2/Vs and 0.003 cm2/Vs from poly(3,4’’’-di(decylthiophenyl) sexithiophene) (PDTST) and poly(3,4”’-di(decylthiophenyl) quaterthiophene) (PDTQT), respectively. PDTQT and PDTST are characterized by UV-vis, DSC, AFM images and GIXD patterns. Increased conformational rotation in the main backbone, caused by intramolecular repulsion between neighboring thiophene units, lowers the HOMO level and introduces remarkable chemical stability in the presence of air as well as increases processability due to high solubility. The high solubility and oxidative stability of PDTST and PDTQT indicate that these side chain conjugation system strategies have the potential for improving other thiophene-based semiconducting polymers.