Polar Side Chain Effects on the Thermoelectric Properties of Benzo[1,2‐b:4,5‐b′]Dithiophene‐Based Conjugated Polymers

Abstract

The molecular structure of polymers has a great influence on their thermoelectric properties; however, the relationship between the molecular structure of a polymer and its thermoelectric properties remains unclear. In this work, two benzo[1,2‐b:4,5‐b′]dithiophene (BDT)‐based conjugated polymers are designed and synthesized, which contain alkyl side chains or polar side chains. The effects of the polymer side chain on the physicochemical properties are systematically investigated, especially the thermoelectric performance of the polymers after doping with 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone and 2,3,5,6‐tetrafluoro‐7,7,8,8‐tetracyanoquinodimethane. It is found that the BDT‐based conjugated polymer with polar side chains exhibits good miscibility with the dopants, leading to higher thermoelectric properties than those of the polymer with alkyl side chains. This work can serve as a reference for the future design of high‐performance organic thermoelectric polymers.

A review on recent developments of thermoelectric materials for room-temperature applications

“…The effect of both dopant type and polymer structure on the PF was underlined in the work of Conversely, Pan et al [73] proved that the molecular structure of polymers also has a remarkable influence on the PF of polymers. The authors focused on the effect of polymer side chain on the thermoelectric performance of two benzo[1,2-b:4,5-b′]dithiophene (BDT)-based conjugated polymers.…”

Correlation of Thermoelectric Performance, Domain Morphology and Doping Level in PEDOT:PSS Thin Films Post‐Treated with Ionic Liquids

“…[ 8–10 ] Commonly used conductive polymers are usually based on a conjugated backbone structure, like in polyacetylene, polypyrrole, polyaniline, or polythiophene. [ 11 ] With different techniques of doping, [ 12–14 ] side chain variations, [ 14 ] or backbone modifications [ 15 ] the thermoelectric performance can be positively influenced.…”

Studies on the Doping Mechanism of Conjugated Thienothiophene Polymer/MWCNT Hybrids for Thermoelectric Application

“…[ 19,20 ] Recently, significant progress has been made in studying the relationship between polymer structure and TE properties. [ 21,22 ] Wang et al. designed and synthesized donor‐acceptor (D–A) type conjugated polymers and effectively enhanced their TE properties through side‐chain engineering.…”