PEDOT修饰的石墨烯@聚苯胺复合材料的制备及热电性能研究

发布时间：2018-04-16 16:38

  本文选题：PEDOT + 石墨烯微片　； 参考：《哈尔滨工业大学》2016年硕士论文

【摘要】：导电聚苯胺因其具有多重导电态、独特的掺杂机制和较低的热导率,成为聚合物热电材料的研究热点。通过酸掺杂、与聚合物、碳材料复合等方法,都能使聚苯胺的导电性能得到提升,并且保持低的热导率,从而使聚苯胺的热电性能得到提升。本文通过向聚苯胺中加入聚3,4-乙烯二氧噻吩修饰的石墨烯微片(PEDOT-GN)作为导电填料,研究了PEDOT:GN的比例和PEDOT-GN加入量对聚苯胺复合材料热电性能的影响,并考察了掺杂酸的性质对聚苯胺复合材料的结构形貌及热电性能的影响。石墨烯微片易团聚,在其表面修饰聚3,4-乙撑二氧噻吩:聚苯乙烯磺酸(PEDOT:PSS)可提高石墨烯微片在聚苯胺基体中的分散性。扫描电镜照片显示,PEDOT:PSS纳米线及PEDOT纳米点修饰在石墨烯微片上或桥接于石墨烯微片之间,构筑了大量多维导电网络。加入PEDOT修饰的石墨烯微片后,由XRD图可知,复合材料的结晶性变好;由红外光谱、拉曼光谱可知,复合材料内部未生成新的化学键。由热失重曲线可知,加入PEDOT-GN后,复合材料的热稳定性增加,说明PEDOT-GN可减降低聚苯胺脱掺杂的程度。硫酸作为掺杂酸时聚苯胺包覆的聚3,4-乙烯二氧噻吩修饰的石墨烯微片(记为PEDOT-GN@PANS)复合材料在所测试范围内的热稳定性最好。掺杂酸为盐酸和磺基水杨酸时对PEDOT:PSS中PSS的脱去效果较好。研究了掺杂酸为硫酸,导电剂PEDOT-GN的PEDOT:GN比例和加入量对聚苯胺复合材料热电性能的影响。研究表明,加入PEDOT-GN后,复合材料的电导率在测试范围内随PEDOT和PEDOT-GN含量的增加而增大,其中,当PEDOT与GN的比例为1:2时,加入量为20%的试样电导率最高,在180℃时可达1956 S/cm,比聚苯胺提高了30倍;复合材料的Seebeck系数在测试范围内的温度稳定性均比聚苯胺好,且随着PEDOT和PEDOT-GN含量的增加而改善;虽然复合材料的热导率随着PEDOT:GN比例和PEDOT-GN加入量的增加而增大,但其热导率仍在0.4 W/(m·K)以下。当PEDOT:GN=1:2、PEDOT-GN=20%时,复合材料的热电性能最好,其ZT值可达1.26×10-3(180℃),比未加PEDOT-GN的聚苯胺提高了12.6倍。另外,研究了盐酸、磺基水杨酸、盐酸-磺基水杨酸混酸、硫酸-磺基水杨酸混酸对聚苯胺复合材料热电性能的影响。研究表明,盐酸-磺基水杨酸为掺杂酸时,聚苯胺复合材料热电性能的改善最显著,当测试温度为180℃时,其ZT值可达2.38×10-3,是PEDOT-GN@PANS复合材料的3.7倍。
[Abstract]:Conductive Polyaniline has become the research hotspot of polymer thermoelectric materials because of its multi-conducting state, unique doping mechanism and low thermal conductivity.The conductivity of Polyaniline can be improved and the thermal conductivity of Polyaniline can be improved by means of acid doping, polymer and carbon composite, so that the thermoelectric properties of Polyaniline can be improved.In this paper, the effect of the ratio of PEDOT:GN and the amount of PEDOT-GN on the thermoelectric properties of Polyaniline composites was studied by adding PEDOT-GNN as conductive filler.The influence of the properties of doped acid on the morphology and thermoelectric properties of Polyaniline composites was investigated.Graphene microchips are easy to agglomerate, and the surface modification of poly (3o 4-ethylenedioxythiophene): polystyrene sulfonic acid (PEDOT: PSS) can improve the dispersity of graphene microchips in Polyaniline matrix.Scanning electron microscope (SEM) photos show that PEDOT: PSS nanowires and PEDOT nanowires are modified on graphene microchips or bridged between graphene microchips, and a large number of multi-dimensional conductive networks have been constructed.With the addition of PEDOT modified graphene microchips, the crystallinity of the composites was improved by XRD, and no new chemical bonds were formed in the composites by IR and Raman spectra.The thermogravimetric curves show that the thermal stability of the composites increases with the addition of PEDOT-GN, which indicates that PEDOT-GN can reduce the degree of dedoping of Polyaniline.Polyaniline coated graphene microchip (PEDOT-GNPANSs) with polyaniline coating as doping acid has the best thermal stability in the tested range.When the doped acid is hydrochloric acid and sulfosalicylic acid, the removal effect of PSS in PEDOT:PSS is better.The effects of PEDOT:GN ratio of conductive agent PEDOT-GN and doping acid as sulfuric acid on the thermoelectric properties of Polyaniline composites were studied.The results show that the conductivity of the composites increases with the increase of PEDOT and PEDOT-GN content in the test range after the addition of PEDOT-GN. When the ratio of PEDOT to GN is 1:2, the conductivity of the composites with 20% addition is the highest.The Seebeck coefficient of the composite is better than that of Polyaniline at 180 鈩，

本文编号：1759789