The development of n-type organic thermoelectrics (OTEs) falls significantly behind that of their p-type counterparts. Herein, two acceptor-acceptor (A-A) polymers, PDCNBT-DPP and PDCNBSe-DPP, were generated by combining strongly electron-deficient cyano-functionalized benzochalcogenadiazole and diketopyrrolopyrrole building blocks, both of which acted as universal moieties for high-mobility polymers. The A-A polymers showed good solubility, low-lying lowest unoccupied molecular orbital (LUMO) energy levels, and narrow bandgaps; thus, predominant n-type characteristics were achieved in organic thin-film transistors. After n-type doping, both polymers exhibited n-type performance, in which the highest conductivity was 12.36 S cm−1 and a large power factor of 9.22 μW m−1 K−2 was obtained in OTE devices. Our study demonstrated that benzochalcogenadiazole is an excellent building block for developing n-type OTE materials. In addition, the A-A strategy provides an avenue for constructing new types of polymers for high-power n-type OTE materials.
Bibliographical noteFunding Information:
X.G. is thankful for the financial support from the Songshan Lake Materials Laboratory (2021SLABFK03) and the Guangdong Provincial Key Laboratory Program (2021B1212040001) from the Department of Science and Technology of Guangdong Province. K.F acknowledges the financial support from the Guangdong Basic and Applied Basic Research Foundation (2021A1515011640), the Shenzhen Basic Research Fund (no. JCYJ20190809162003662) and the National Natural Science Foundation of China (22005135). This work is also supported by the Center for Computational Science and Engineering at Southern University of Science and Technology (SUSTech). The authors acknowledge the assistance of the SUSTech Core Research Facilities.
© 2022, The Author(s), under exclusive licence to The Society of Polymer Science, Japan.
ASJC Scopus subject areas
- Polymers and Plastics
- Materials Chemistry