Volume 250, 2024

High-performance n-type organic thermoelectrics enabled by modulating cyano-functionalized polythiophene backbones

Abstract

The scarcity of n-type polymers with high electrical conductivity (σ) and power factor (PF) is the major challenge for organic thermoelectrics (OTEs). By integrating cyano functionalities and an intramolecular conformation lock, we herein synthesize a new electron-deficient building block, CNg4T2, bearing long 1,4,7,10-tetraoxahendecyl side chains, and then further develop two n-type polythiophene derivatives, CNg4T2-2FT and CNg4T2-CNT2, with 3,4-difluorothiophene and 3,3′-dicyano-2,2′-bithiophene as co-units, respectively. Compared with CNg4T2-2FT, CNg4T2-CNT2 features a deeper-positioned lowest unoccupied molecular orbital (LUMO) while maintaining a high degree of backbone coplanarity. As a consequence, the CNg4T2-CNT2 film with molecular dopant N-DMBI delivered an impressive σ of 13.2 S cm−1 and a high PF of up to 10.84 μW m−1 K−2, significantly outperforming CNg4T2-2FT and benchmark n-type polymer N2200 films. To the best of our knowledge, this PF of CNg4T2-CNT2 devices is the highest value for n-type polythiophenes in OTEs. Further characterizations indicate that the high performance of CNg4T2-CNT2-based devices is attributed to the high doping efficiency and ordered packing of polymer chains. Our study demonstrates that CNg4T2 is a highly appealing electron-deficient building block for n-type OTE polymers and also suggests that fine-tuning of the polymer backbone is a powerful approach to accessing high-performance n-type polymers for OTE devices.

Graphical abstract: High-performance n-type organic thermoelectrics enabled by modulating cyano-functionalized polythiophene backbones

Associated articles

Supplementary files

Article information

Article type
Paper
Submitted
10 jul 2023
Accepted
23 ago 2023
First published
23 ago 2023

Faraday Discuss., 2024,250, 335-347

High-performance n-type organic thermoelectrics enabled by modulating cyano-functionalized polythiophene backbones

J. Wang, S. Ma, S. Y. Jeong, W. Yang, J. Li, Y. W. Han, K. Feng and X. Guo, Faraday Discuss., 2024, 250, 335 DOI: 10.1039/D3FD00135K

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements