纳米PEDOT衍生物热电材料的制备及性能

Thermoelectric (TE) material is a kind of "green" energy conversion materials with wide and promising application prospect. Presently, most studies on TE materials mainly focus on inorganic semiconductors. However, conducting polymers as a novel expansion of TE material field are beginning to attract more and more attention in recent years. Limited reports on organic TE materials mainly focuse on conducting polymer block materials and conducting polymer/inorganic composite materials, theoretical calculations predict that further enhancement of the TE performance can be achieved in nanostructured materials, whereas few research on TE performance of nano conducting polymers is reported up to the present. On the basis of the previous research on poly(3,4-ethylenedioxythiophene) (PEDOT), one of the most classical conducting polymers, and its remarkable conducting properties (>102 S/cm) and high environmental stability, the present work on the TE properties of PEDOT and its derivatives is conducted. The materials with various nano structures of nanotube, nano wire, nano fiber, conducting polymer/inorganic nanocomposite fiber, and nano films of layer structure were prepared by different methods such as electrochemical deposition, spin coating, and electrostatic spinning, and their TE performances were investigated systematically. Further treatment processes toward the resulting nanostructured materials were investigated to enhance the TE performance (ZT ~ 10-1). The information about the scientific basis for the research work of nano conducting polymer TE materials are provided, and the obtained experimental data are also summarized in the following sections.

热电材料是一类具有广泛应用前景的绿色能源转换材料。目前的研究主要以无机半导体热电材料为主。近年来有机热电材料也逐渐成为研究热点，但主要集中于导电高分子块体材料及导电高分子/无机复合材料。理论研究表明，结构纳米化是实现材料热电性能提高的一个有效途径，而国内外对于纳米结构导电高分子材料热电性能的报道甚少。在前期基础上，本课题拟以经典导电高分子PEDOT及其衍生物为研究重点（高电导率和良好环境稳定性，大于102 S/cm），采用各种不同的材料制备方法如电化学沉积、旋涂、静电纺丝等制备基于PEDOT及其衍生物的纳米结构材料（纳米管、纳米线、纳米纤维、有机/无机纳米复合纤维、纳米层状薄膜等）详细研究其热电性能；并采用不同方法对所获纳米结构材料进行后处理以实现材料热电性能的进一步提高，使其热电优值（ZT）达到10-1。同时总结规律，为纳米导电高分子热电材料的深入研究提供一定的科学依据。

本项目申请目的是以经典导电高分子PEDOT及其衍生物为研究重点，采用各种不同的材料制备方法如电化学沉积、旋涂等制备基于PEDOT及其衍生物的纳米结构材料（如有机/无机纳米复合物、纳米层状薄膜等），详细研究其热电性能；采用不同方法对所获纳米结构材料进行后处理以实现材料热电性能的进一步提高，使其热电优值（ZT）达到10-1，同时总结规律，为纳米导电高分子热电材料的深入研究提供一定的科学依据。三年预定目标为：取得具有独立知识产权的成果，三年内预计发表SCI论文3-5篇。从项目的运行情况来看，顺利完成原定计划。首先基于旋涂法和溶剂蒸汽热处理方式制备了高电导率的PEDOT衍生物PEDOT:PSS薄膜，并采用不同的后处理方法来进一步改善其热电性能；同时，将高电导率、良好电化学稳定性的PEDOT:PSS纳米薄膜作为工作电极成功应用于电化学聚合，制备了层状结构的纳米薄膜材料，对其热电性能进行了系统研究；此外，我们还制备了PEDOT衍生物与CNT、Bi2Te3、Fe3O4的纳米复合热电材料，并进行了结构表征和热电性能研究，其中真空抽滤法制备的PEDOT:PSS/SWCNT纳米复合薄膜材料的热电性能实现了热电优值10-1的突破；在前期研究工作的基础上，我们总结了影响PEDOT:PSS薄膜。电导率和热电性能的各种因素，形成了在该研究领域具有指导意义的综述论文。在基金资助下，2013-2015年共计发表SCI论文22篇（其中影响因子大于3.0的SCI论文5篇，封面论文2篇，被国际科技评论网站点评2篇），获江西省高等学校科技成果一等奖等奖励，参加国际学术会议5次。这些成果的取得不仅探讨了纳米导电高分子的热电性能，也为导电高分子热电材料的应用奠定了一定基础。