Organic Transistors Based on Highly Crystalline Donor-Acceptor π-Conjugated Polymer of Pentathiophene and Diketopyrrolopyrrole

• Published in: Molecules (Basel, Switzerland) Switzerland), 2024-01, Vol.29 (2), p.457
• Main Authors: Ren, Shiwei, Wang, Zhuoer, Chen, Jinyang, Wang, Sichun, Yi, Zhengran
• Format: Article
• Language: English
• Subjects: donor–acceptor; Electric properties; Field-effect transistors; hole mobility; Molecular structure; Molecular weight; organic electronics; Polymers; Semiconductors; solution processing; Transistors; π-conjugated polymer material
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/molecules29020457

Oligomers and polymers consisting of multiple thiophenes are widely used in organic electronics such as organic transistors and sensors because of their strong electron-donating ability. In this study, a solution to the problem of the poor solubility of polythiophene systems was developed. A novel π-conjugated polymer material, PDPP-5Th, was synthesized by adding the electron acceptor unit, DPP, to the polythiophene system with a long alkyl side chain, which facilitated the solution processing of the material for the preparation of devices. Meanwhile, the presence of the multicarbonyl groups within the DPP molecule facilitated donor-acceptor interactions in the internal chain, which further improved the hole-transport properties of the polythiophene-based material. The weak forces present within the molecules that promoted structural coplanarity were analyzed using theoretical simulations. Furthermore, the grazing incidence wide-angle X-ray scanning (GIWAXS) results indicated that PDPP-5Th features high crystallinity, which is favorable for efficient carrier migration within and between polymer chains. The material showed hole transport properties as high as 0.44 cm V s in conductivity testing. Our investigations demonstrate the great potential of this polymer material in the field of optoelectronics.