Cost-efficient quinoxaline-based semiconducting polymers: systematic structure-property-morphology correlation toward reliable organic field-effect transistors

Abstract

Achieving low-cost, organic semiconducting polymers remains a key challenge for the practical application of organic field-effect transistors (OFETs). To overcome this issue, quinoxaline has attracted considerable attention due to its unique structural advantages and synthetic feasibility. In this study, a series of quinoxaline-based semiconducting polymers were successfully synthesized through systematic tuning of -linkers and alkyl side chains, with comprehensive evaluation of their OFET performance. Density functional theory calculations revealed that these polymers exhibit highly planar backbone structures stabilized by intramolecular noncovalent interactions. Among the synthesized polymers, a thiophene-linker-incorporated polymer with a short alkyl chain exhibited a hole mobility of 2.42 × 10−2 cm2 V−1 s−1, representing an improvement of nearly one order of magnitude over conventional PTQ10-based OFETs. Furthermore, the introduction of a fluorinated bithiophene unit as the -type linker enabled ambipolar charge transport. Grazing-incidence wide-angle X-ray scattering (GIWAXS) results further revealed that all polymers exhibited edge-on orientations conductive to efficient charge transport in OFETs. Collectively, this study provides insights into structure–property–morphology relationships in quinoxaline-based polymers with low synthetic complexity, providing rational molecular design guidelines for scalable semiconducting polymer materials.