Thermoelectric and mechanical performances of ionic liquid-modulated PEDOT:PSS/SWCNT composites at high temperatures

Abstract

Significant progress has been achieved for flexible polymer thermoelectric (TE) composites in the recent decade due to their potential application in wearable devices and sensors. In sharp contrast with the booming TE studies at room temperature, the TE performances of polymer TE composites received relatively less attention despite the significance for the application of TE composites in the high temperature environments. The TE and mechanical performances of flexible poly (3,4 ethylenedioxythiophene):poly(styrene sulfonate)/single-walled carbon nanotube (PEDOT:PSS/SWCNT) composite films with ionic liquid (IL) (refer to as “PEDOT:PSS/SWCNT-IL”) at high temperatures are studied in the present work. The resultant composite film shows the increasing TE performances with increasing temperatures and SWCNT contents. The maximum value of the power factor reaches 301.35 W m-1 K-2 at 470 K for the PEDOT:PSS/SWCNT-IL composite. Besides, the addition of IL can improve the elongation at break of composites compared to the IL-free composites. This work promotes the advance of flexible polymer TE composites and widens the potential applications at different temperature ranges.

Tuning the mechanical and thermoelectric properties of self‐standing stretchable PEDOT:PSS/SDBS films

“…The results reported here imply that enhancing the annealing temperature can increase the films elongation at break, possibly owing to the accelerated relaxation of polymer chains at elevated temperatures. 69,77 Meanwhile, temperature above a particular threshold causes deterioration or structural alterations that compromise mechanical stability. This degradation could include the breakdown of molecular bonds or the beginning of thermal decomposition, both of which result in a decrease in mechanical characteristics.…”

Ultrafast and Cost-Effective Fabrication of High-Performance Carbon-Based Flexible Thermoelectric Hybrid Films and Their Devices

“…The raw materials are all industrially available, and the fabrication route is based on a facile hot-pressing way without any solution, therefore exhibiting outstanding cost-effective and efficient fabrication features. Figure b,c compares the calculated ratios for S 2 σ/cost and S 2 σ/fabrication time between the as-fabricated EG 70 CF 27 PF 3 IL 6 film in this work and other conventional carbon-based thermoelectric materials including composites based on partial EG and carbon nanotubes (CNTs). − Here, the S 2 σ/cost indicates the unit cost money ($) of the achieved peak S 2 σ (μW m –1 K –2 ), and the S 2 σ/time indicates the unit cost time for fabrication (min) of the achieved peak S 2 σ (μW m –1 K –2 ). The data of cost money are derived from the market research, while the data of cost time for fabrication are mainly derived from the reported literature. − In this work, the S 2 σ/cost parameter of 148.8 μW g m –1 K –2 $ –1 and the S 2 σ/time parameter of 2.58 μW m –1 K –2 min –1 are both significantly competitive.…”

“…Figure b,c compares the calculated ratios for S 2 σ/cost and S 2 σ/fabrication time between the as-fabricated EG 70 CF 27 PF 3 IL 6 film in this work and other conventional carbon-based thermoelectric materials including composites based on partial EG and carbon nanotubes (CNTs). − Here, the S 2 σ/cost indicates the unit cost money ($) of the achieved peak S 2 σ (μW m –1 K –2 ), and the S 2 σ/time indicates the unit cost time for fabrication (min) of the achieved peak S 2 σ (μW m –1 K –2 ). The data of cost money are derived from the market research, while the data of cost time for fabrication are mainly derived from the reported literature. − In this work, the S 2 σ/cost parameter of 148.8 μW g m –1 K –2 $ –1 and the S 2 σ/time parameter of 2.58 μW m –1 K –2 min –1 are both significantly competitive. Besides, to evaluate the application potential of the as-designed composite films, a homemade thermoelectric device based on the performance-optimized films is designed (Figure d).…”

“…Here, the four main components EG, CF, PF, and IL are abbreviated from expanded graphite, CF, phenolic resin, and ionic liquid, respectively. Comparison of the calculated ratios of (b) S 2 σ/cost and (c) S 2 σ/time of the as-fabricated EG 70 CF 27 PF 3 IL 6 film with other conventional carbon-based thermoelectric materials including composites based on partial EG and CNTs. − Here, S 2 σ is the power factor of the as-fabricated composite films and the time in (b) takes no account of the drying time. (d) Photo of EG 70 CF 27 PF 3 IL 6 film-based devices.…”

Energy harvesting through thermoelectrics: topological designs and materials jetting technology

“…Besides harvesting waste heat from factories, heat from photovoltaic cells [4] and high-power light-emitting diodes [5] have also shown potential for energy conversion through TE devices. On a smaller scale, a small temperature difference between the human body heat (waste heat energy) and the environment is also able to generate usable energy to power wearable electronic devices [6][7][8][9][10][11][12] .…”