| 초록 |
Organic field-effect transistors (OFETs) with conjugated polymers have been widely studied with the advantages of their great potential for large-area, flexible, and low-cost. Recently, halogenated isoindigo has emerged as an acceptor unit due to the deep-lying LUMO energy level leading to enhanced n-type characteristics. In particular, chlorination is the effective strategy because of short synthesis steps and the accommodation of high electron density, compared to fluorination. However, the chlorine atom could induce backbone distortion because of its large size. Therefore, we synthesized conjugated polymers with asymmetric mono-chlorinated isoindigo via Stille copolymerization. In the polymer backbone, the mono-chlorinated isoindigo causes less steric hindrance relative to existing di-chlorinated isoindigo. Additionally, they could induce the dipole moment which results in improved crystallinity. Finally, the polymers were applied to OFETs as an active layer and characterized. |
