Tunable Thermoelectric Performance of the Nanocomposites Formed by Diketopyrrolopyrrole/Isoindigo-Based Donor-Acceptor Random Conjugated Copolymers and Carbon Nanotubes

Kuan-Chieh Wang; Po-Shen Lin; Yan-Cheng Lin; Shih-Huang Tung; Wen-Chang Chen; Cheng-Liang Liu

doi:10.1021/acsami.3c11792

Tunable Thermoelectric Performance of the Nanocomposites Formed by Diketopyrrolopyrrole/Isoindigo-Based Donor-Acceptor Random Conjugated Copolymers and Carbon Nanotubes

ACS Appl Mater Interfaces. 2023 Dec 6;15(48):56116-56126. doi: 10.1021/acsami.3c11792. Epub 2023 Nov 27.

Authors

Kuan-Chieh Wang¹, Po-Shen Lin¹, Yan-Cheng Lin^{2

3}, Shih-Huang Tung⁴, Wen-Chang Chen^{3

5}, Cheng-Liang Liu^{1

3}

Affiliations

¹ Department of Materials Science and Engineering, National Taiwan University, Taipei 10617, Taiwan.
² Department of Chemical Engineering, National Cheng Kung University, Tainan 70101, Taiwan.
³ Advanced Research Center of Green Materials Science and Technology, National Taiwan University, Taipei 10617, Taiwan.
⁴ Institute of Polymer Science and Engineering, National Taiwan University, Taipei 10617, Taiwan.
⁵ Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan.

PMID: 38010815
DOI: 10.1021/acsami.3c11792

Abstract

This paper presents the development of thermoelectric properties in nanocomposites comprising donor-acceptor random conjugated copolymers and single-walled carbon nanotubes (SWCNTs). The composition of the conjugated polymers, specifically the ratio of diketopyrrolopyrrole (DPP) to isoindigo (IID), is manipulated to design a series of random conjugated copolymers (DPP0, DPP5, DPP10, DPP30, DPP50, DPP90, DPP95, and DPP100). The objective is to improve the dispersion of SWCNTs into smaller bundles, leading to enhanced thermoelectric properties of the polymer/SWCNT nanocomposite. This dispersion strategy promotes an interconnected conducting network, which plays a critical role in optimizing the thermoelectric performance. Accordingly, the effects of morphologies on the thermoelectric properties of the nanocomposites are systematically investigated. The DPP95/SWCNT nanocomposite exhibits the strongest interaction, resulting in the highest power factor (PF) of 711.1 μW m^-1 K^-2, derived from the high electrical conductivity of 1690 S cm^-1 and Seebeck coefficient of 64.8 μV K^-1. The prototype flexible thermoelectric generators assembled with a DPP95/SWCNT film achieve a maximum power output of 20.4 μW m^-2 at a temperature difference of 29.3 K. These findings highlight the potential of manipulating the composition of random conjugated copolymers and incorporating SWCNTs to efficiently harvest low-grade waste heat in wearable thermoelectric devices.

Keywords: carbon nanotubes; conjugated polymers; donor−acceptor; nanocomposite; thermoelectrics.