Recent Development of Thermoelectric Polymers and Composites

Abstract

Thermoelectric materials can be used as the active materials in thermoelectric generators and as Peltier coolers for direct energy conversion between heat and electricity. Apart from inorganic thermoelectric materials, thermoelectric polymers have been receiving great attention due to their unique advantages including low cost, high mechanical flexibility, light weight, low or no toxicity, and intrinsically low thermal conductivity. The power factor of thermoelectric polymers has been continuously rising, and the highest ZT value is more than 0.25 at room temperature. The power factor can be further improved by forming composites with nanomaterials. This article provides a review of recent developments on thermoelectric polymers and polymer composites. It focuses on the relationship between thermoelectric properties and the materials structure, including chemical structure, microstructure, dopants, and doping levels. Their thermoelectric properties can be further improved to be comparable to inorganic counterparts in the near future.

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

“…The combustion of traditional fossil fuels has caused changes in the global climate that have prompted people to seek green energy materials. Thermoelectric materials, which can realize the direct conversion between thermal energy and electrical energy depending on the mobility of charge carriers, have attracted considerable attention as a green option for various applications ranging from harvesting waste heat to microprocessor cooling . Thermoelectric conversion efficiency is usually evaluated by a dimensionless figure of merit ( ZT ), which is defined as ZT = S 2 σT/κ, where S is the Seebeck coefficient; σ and T stand for electrical conductivity and absolute temperature, respectively; and κ is the thermal conductivity.…”

Assembly Strategy and Performance Evaluation of Flexible Thermoelectric Devices

“…[1][2][3][4][5][6] One main reason lies in the high flexibility of the TE devices, which can meet the severe [1][2][3][4][5][6] One main reason lies in the high flexibility of the TE devices, which can meet the severe…”

“…[1][2][3][4][5][6] One main reason lies in the high flexibility of the TE devices, which can meet the severe In this study, we report a comparison of the three main assembly strategies for flexible TE devices (serial, stacking, and folding), and put forward a convenient and general evaluation method for flexible device performance (FDP). [1][2][3][4][5][6] One main reason lies in the high flexibility of the TE devices, which can meet the severe In this study, we report a comparison of the three main assembly strategies for flexible TE devices (serial, stacking, and folding), and put forward a convenient and general evaluation method for flexible device performance (FDP).…”

“…[21][22][23][24] Here, we focus on the film assembly configuration, since this is the most extensively studied one till now. [1][2][3][4][5][6] One main reason lies in the high flexibility of the TE devices, which can meet the severe In essential, the assembly modes can be divided into three major strategies, namely, (b) serial, (c) folding, and (d) stacking routes.…”

The Cross‐Linking Effect on the Thermoelectric Properties of Conjugated Polymer/Carbon Nanotube Composite Films

“…The efficiency with which a material converts a thermal gradient to electrical energy depends on the figure of merit ( ZT = S 2 σT /κ), where S , σ, T , and κ are Seebeck coefficient, electrical conductivity, absolute temperature, and thermal conductivity, respectively . As the carrier concentration ( n ) increases, typically, σ and κ increase and S decreases . Thus, to obtain high ZT , it is essential to optimize the parameters correlated to the n of the material …”