Article

Improved Thermoelectric Behavior of Nanotube-Filled Polymer Composites with Poly(3,4-Ethylenedioxythiophene) Poly(Styrenesulfonate)

Department of Mechanical Engineering, Texas A&M University, College Station, Texas 77843, USA.
ACS Nano (Impact Factor: 12.88). 01/2010; 4(1):513-23. DOI: 10.1021/nn9013577
Source: PubMed

ABSTRACT

The thermoelectric properties of carbon nanotube (CNT)-filled polymer composites can be enhanced by modifying junctions between CNTs using poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS), yielding high electrical conductivities (up tõ40000 S/m) without significantly altering thermopower (or Seebeck coefficient). This is because PEDOT:PSS particles are decorated on the surface of CNTs, electrically connecting junctions between CNTs. On the other hand, thermal transport remains comparable to typical polymeric materials due to the dissimilar bonding and vibrational spectra between CNT and PEDOT:PSS. This behavior is very different from that of typical semiconductors whose thermoelectric properties are strongly correlated. The decoupled thermoelectric properties, which is ideal for developing better thermoelectric materials, are believed to be due to thermally disconnected and electrically connected contact junctions between CNTs. Carrier transport at the junction is found to be strongly dependent on the type and concentration of stabilizers. The crucial role of stabilizers was revealed by characterizing transport characteristics of composites synthesized by electrically conducting PEDOT:PSS and insulating gum Arabic (GA) with 1:1-1:4 weight ratios of CNT to stabilizers. The influence of composite synthesis temperature and CNT-type and concentration on thermoelectric properties has also been studied. Single-walled (SW) CNT-filled composites dried at room temperature followed by 80 °C exhibited the best thermoelectric performance in this study. The highest thermoelectric figure of merit (ZT) in this study is estimated to bẽ0.02 at room temperature, which is at least one order of magnitude higher than most polymers and higher than that of bulk Si. Further studies with various polymers and nanoparticles with high thermoelectric performance may result in economical, lightweight, and efficient polymer thermoelectric materials.

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Available from: Yeon Seok Kim, Mar 07, 2014
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    • "Yu et al. [27,59,60] reported a series of investigations of PEDOT:PSS/CNT TE composites. The first report of the PEDOT:PSS/ CNT TE composites appeared in 2010, prepared using PEDOT:PSS doped with DMSO and insulating gum Arabic (GA) [59]. Because the functionalization of PEDOT:PSS particles on the CNT surface led to electrically connecting junctions between CNTs, the composite electrical conductivities were enhanced significantly. "
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    ABSTRACT: Being green energy materials, thermoelectric (TE) materials can realize direct energy conversions between heat and electricity, thus have widely applications in both TE generators for energy harvesting and local cooling. Especially, low-quality waste heat can be conveniently used. In the recent several years, there is rapidly growing interest in organic conducting polymer/carbon particle TE composites, which synergistically combine the advantages of both carbon particles and polymer materials. In this review, the recent progress is systematically summarized in the order of the dimensionality of the carbon particles (2D, 1D and 0D) and the type of polymer matrix. Synergistic effect and polymer ordered structure, morphological tuning, devices and flexible films are highlighted. Finally, prospects and suggestions for future studies are presented.
    Full-text · Article · Jan 2016 · Composites Science and Technology
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    • "For polymer-based thermoelectric materials to achieve a ZT that is comparable to that of inorganic thermoelectric materials, it is essential to enhance the Seebeck coefficient without decreasing the electrical conductivity. For this reason, numerous researchers have suggested organic/inorganic composites such as poly(3,4-ethylenedioxythiophene): poly(4-styrenesulfonate) (PEDOT:PSS)/carbon nanotubes (CNTs) [16], PEDOT:PSS/Te nanorods [19], PEDOT:PSS/Ca 3 Co 4 O 9 [20], PEDOT:PSS/ PbTe [21], PEDOT:PSS/Bi 2 Te 3 [7] [22], P 3 HT/Bi 2 Te 3 [25], and polyaniline (PANI)/CNTs [26] to achieve better thermoelectric performance. We herein suggest a quick, simple, and high-yielding synthesis method for preparing PEDOT:PSS/Ge composite films for use as thermoelectric "
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    ABSTRACT: We herein report on the enhanced thermoelectric properties of poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS)/Ge composite films fabricated by drop-casting of a solution of Ge powder in PEDOT:PSS. The power factor of the fabricated PEDOT:PSS/Ge composite films with 29.6 wt.% Ge was 165 μW m− 1K− 2, and they exhibited an extremely low thermal conductivity. The maximum thermoelectric figure of merit was anticipated to be ~ 0.1 at room temperature for the PEDOT:PSS/Ge composite films with 29.6 wt.% Ge, suggesting that their heterostructure was effective in enhancing their thermoelectric efficiency.
    Full-text · Article · Sep 2014 · Thin Solid Films
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    • "Carbon nanotubes (CNTs), consisting of graphitic sheets rolled up into a cylindrical shape, are often used as templates in such syntheses [10] [11]. Up to now, several synthetic procedures have been reported for the synthesis of PEDOT/CNTs nanocomposites, such as the solid state mixing of both powder components, the mixture of dispersions of each component [12], the electrochemical polymerization of 3,4-ethylenedioxythiophene (EDOT) over a CNTs-based electrode [13] and in situ chemical polymerization of EDOT in CNTs suspensions [14]. However, these routes generally yielded insoluble powders and, moreover, these composites showed irregular "
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    ABSTRACT: Core-shell structured poly(3,4-ethylenedioxythiophene)/multi-walled carbon nanotubes (PEDOT/MWCNTs) nanofibers were synthesized through an interfacial polymerization technique. The interfacial polymerization at a liquid-liquid interface allowed PEDOT to grow uniformly on the surface of MWCNTs due to the presence of pi-pi interactions between PEDOT and MWCNTs walls. The morphology, structure and composition of the as-prepared PEDOT/MWCNTs were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy and Fourier transform infrared spectroscopy (FT-IR). In addition, the electrocatalytic properties of PEDOT/MWCNTs toward redox reactions of magnolol, a widely used traditional Chinese medicine, were systematically investigated. The results showed that the PEDOT/MWCNTs nanofibers exhibited a distinctly higher activity for the detection of magnolol compared with those of pure MWCNTs and PEDOT. The remarkably enhanced activity for the nanofibers can be attributed to the unique configuration and synergistic contribution between PEDOT and MWCNTs. The presented method is a general, facile and green approach for the synthesis of polymer/CNTs nanofibers, which is significant for the development of high performance electrocatalysts for biosensing and fuel cell applications.
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