基于单壁碳纳米管与有机小分子复合制备N型有机热电材料

发布时间：2018-04-28 01:31

  本文选题：热电性质 + 单壁碳纳米管　； 参考：《青岛科技大学》2017年硕士论文

【摘要】：在化石能源即将枯竭的背景下,能源的有效利用显得至关重要,然而人类工业生产和日常生活产生的热能大部分以扩散形式被浪费掉。热电材料是一种能将热能直接转化为电能的材料,吸引着人们研究它并将其用于能量回收。近年来,有机/无机复合的热电材料相比较于无机热电材料,具有柔性好、热导率低、成本低、无移动相或流体,从而引起人们的极大关注。迄今为止p型有机/无机复合热电材料的发展已经取得巨大进步,然而发展n型有机/无机复合热电材料依然面对巨大的挑战。本文的研究工作主要集中在基于单壁碳纳米管与有机小分子复合制备n型热电材料,包括以下三部分内容:1、我们利用SWCNT与有机小分子DETA通过溶液共混的方法制备了SWCNT/DETA复合材料,然后通过CaH2再次还原得到一种高性能的n型复合热电材料。该材料Seebeck系数和电导率分别为-41.0±1.5μV K-1,160±10 S cm-1。我们利用扫描电子显微镜和吸收红外光谱对复合材料的微观形貌和组分进行了表征,并且阐释了单壁碳纳米管经过掺杂由p型导电转变为n型导电的机理模型,用以指导材料的掺杂。最后我们基于该材料制备了性能优异的热电器件,经过测试,由14个p-n结构成的热电器件在温度梯度为55 K条件下,可产生62 mV的开路电压和649 nW输出功率。2、设计合成了有机导电小分子傒酰亚胺(PDINE)、萘酰亚胺(NDINE)并制备了具有n型特性的SWCNT/PDINE和SWCNT/NDINE纳米复合材料。较高的电导率和Seebeck系数使得材料展现出非常高的PF值(135?14μW m-1 K-2),在当前n型有机热电材料中最高的性能之一。然后我们利用该材料构成五个p-n结的热电器件,经过测试,该器件在温度梯度为50 K下,展现出很大的输出功率3.3μW。同时我们还利用了热重分析,测试了复合材料的热稳定性,相比较于其他有机热电材料,这种n型有机热电复合材料具耐高温特性(≥200℃),极大拓展了材料的应用温度范围。3、简单制备了基于氧化还原反应的SWCNT/PMMA复合水凝胶温差热电池材料,不仅仅避免了温差热电池液态电解液造成使用上的不方便,而且由于SWCNT的增强作用提供了复合材料的更好的机械性能。同时SWCNT给体系所带来的网络结构渗透过滤效应、表面极化等促进了Sn2+/Sn4+氧化还原对迁移,使得热电池材料展现出了较大的Seebeck系数(1200μV K-1)和电导率(0.11 S cm-1)。
[Abstract]:Under the background that fossil energy is about to be exhausted, the effective utilization of energy is very important. However, most of the heat energy produced by human industrial production and daily life is wasted in the form of diffusion. Thermoelectric material is a kind of material which can convert heat energy directly into electric energy, which attracts people to study it and use it for energy recovery. In recent years, compared with inorganic thermoelectric materials, organic / inorganic composite thermoelectric materials have the advantages of good flexibility, low thermal conductivity, low cost and no moving phase or fluid. So far, great progress has been made in the development of p-type organic / inorganic composite thermoelectric materials, but the development of n-type organic / inorganic composite thermoelectric materials still faces great challenges. In this paper, we mainly focus on the preparation of n-type thermoelectric materials based on single-walled carbon nanotubes and organic small molecules, including the following three parts: 1. We prepared SWCNT/DETA composites by solution blending with SWCNT and organic small molecules DETA. Then a high performance n-type composite thermoelectric material was obtained by CaH2 rereduction. The Seebeck coefficient and conductivity are -41.0 卤1.5 渭 V K-1160 卤10S cm-1, respectively. The microstructure and composition of the composites were characterized by scanning electron microscopy (SEM) and absorption infrared spectroscopy (IR), and the mechanism model of the transition from p-type conduction to n-type conduction of single-walled carbon nanotubes was explained. Used to guide the doping of materials. Finally, we have fabricated thermoelectric devices with excellent performance based on the material. After testing, the thermoelectric devices with 14 p-n structures are fabricated at a temperature gradient of 55 K. The open circuit voltage of 62mV and the output power of 649nW were obtained. The organic conductive small molecular molecules, SWCNT/PDINE and SWCNT/NDINE nanocomposites with n-type properties were designed and synthesized. The high conductivity and Seebeck coefficient make the material exhibit a very high PF value of 135V 14 渭 W m-1 K-2O, which is one of the highest properties in n-type organic thermoelectric materials. Then we use the material to form five p-n junction thermoelectric devices. The test results show that the device has a high output power of 3.3 渭 W at a temperature gradient of 50 K. At the same time, we also used thermogravimetric analysis to test the thermal stability of the composite, compared with other organic thermoelectric materials. The n-type organic thermoelectric composite has the characteristics of high temperature resistance (鈮，

本文编号：1813195