MWNTs/PANI/PVDF复合热电材料的制备及特性研究

Abstract

为开发新型有机聚合物热电材料，本文通过将不同重量百分比的多壁碳纳米管(MWNTs)、聚苯胺(PANI)导电聚合物与聚偏二氟乙烯(PVDF)有机聚合物三种材料进行超声分散并混合后，将其喷涂于聚对苯二甲酸乙二酯(PET)塑料片上，制备出了MWNTs/PANI/PVDF涂层型复合热电材料。实验表明，这种新型热电材料充分利用了均匀分散于复合体中的大量MWNTs及PANI导电聚合物颗粒，提高了复合体的导电特性。同时，利用MWNTs因交叉、链接及三种材料相互复合嵌套产生的大量界面势垒对声子及低能电子的散射效应及弥散于MWNTs及PANI之间的PVDF聚合物颗粒具有的低导热特性，使复合热电材料的塞贝克(Seebeck)系数及热电优值比单纯的碳管/聚合物热电材料有一定提高。研究结果对探索开发新型复合热电材料具有重要的参考价值。 For the development of new organic polymer thermoelectric materials, multi-walled carbon na-notubes (MWNTs), conducting polyaniline (PANI) and polyvinylidene fluoride (PVDF) polymer materials were ultrasonic mixed with different weight ratio and sprayed them to the surface of polyethylene terephthalate (PET) plastic sheets. A new-type MWNTs/PANI/PVDF polymeric ther- moelectric composite coatings was prepared. And the test showed that the synthesized composite thermoelectric coating materials were of interest for several reasons. 1) For the introduction of one-dimensional conducting pathways of the MWNTs and the PANI conductive particles, the elec-trical conductivity of composite is dramatically increased. 2) By adding the MWNTs and PANI particles into the PVDF polymer, a lot of interfacial potential barriers such as tube-tube junctions and scattering point for phonon and lower energy electrons among the MWNTs, PANI particles, and the PVDF polymer were introduced into composite matrix. As a result, the Seebeck coefficient and ZT value of the composite thermoelectric materials were enhanced obviously than the corresponding data of simplest carbon nanotube based organic thermoelectric composites. The research results could provide the important basis for the applications of new-type composite thermoelectric materials.