导电聚合物基柔性固态超级电容器的组装及性能研究

发布时间：2018-12-30 21:15

【摘要】：个人消费电子器件消耗量的日益增加以及可穿戴电子学的进步推动了高性能能量存储器件的快速发展。超级电容器作为一类新型能量存储器件，具有比传统的静电电容器更高的能量密度和比电池更高的功率密度。固态超级电容器将电极、固态电解质以及隔膜集成为一个整体，相比于液态电解质超级电容器，具有质量较轻、易于封装、安全性高、柔韧性好等优点。纸基电子学器件因其成本低廉，具有柔性，环境友好，易于集成等特点，具有很大的研究和应用前景。纸是由直径约为20m的纤维素纤维组成，这些纤维素纤维包含许多由直径数十纳米的纤维组成的微纤维，从而使得纸具有粗糙多孔的表面。这种粗糙多孔的表面对于超级电容器而言，是一种天然的优势，它有利于电化学活性材料附着到纤维素的表面。导电聚合物如聚吡咯（PPy）、聚苯胺（PANI）是一类导电性聚合物材料，具有独特的结构和优异的物理与化学特性，易于合成，电化学活性高，导电性好，成本低廉，适宜作为超级电容器的电极，成为近几年来超级电容器研究的新热点。本论文围绕聚合物基纸基柔性超级电容器电极材料的制备、器件的组装开展了一系列深入细致的研究。通过铅笔涂敷导电石墨与电沉积的方法制备了石墨/PANI复合柔性电极，通过“浸泡-聚合法”制备了PPy/Paper复合柔性电极，两种方法都切实可行，并可推广到其他材料体系的电极制备中，具有广泛的应用价值。通过循环伏安、恒流充放电以及电化学阻抗谱等测试对合成电极的电化学性质进行了详细的探究。现将主要结论总结如下： 1.通过铅笔涂覆的工艺在普通打印纸上沉积一薄层石墨，制备了石墨导电纸，通过电沉积方法在石墨表面沉积PANI，制备了三维多孔石墨/PANI柔性复合纸电极，并系统研究了该电极的电化学性能及其在超级电容器方面的应用。研究表明：该电极化学性质稳定，方阻仅为32.3/sq，在电流密度0.5mA/cm2下其面电容可达到355.6mF/cm2。由石墨/PANI纸电极组装的对称性柔性固态超级电容器重量仅为30.8mg，在体积电流密度4.57mA/cm3下，体积电容为3.55F/cm3，在功率密度0.054W/cm3下，，能量密度为0.32mWh/cm3。该固态器件充放电10000个循环后，电容仍保持83%。 2.采用“浸泡-聚合法”制备了聚吡咯包覆的纸电极，PPy/Paper复合电极具有优异的电学性能，方阻低至4.5/sq，电导率达到15S/cm，具有良好的柔韧性，可弯曲180°，并且电学性能和电化学性能几乎不发生变化。将该电极作为电极分别组装了三明治结构和平面叉指结构的柔性固态超级电容器，研究了相应固态器件的电化学性能。柔性三明治结构固态超级电容器的面电容为0.42F/cm2，在0.27W/cm3功率密度下，能量密度可达到1mWh/cm3，揭示了其在柔性能量存储领域的巨大应用价值。
[Abstract]:The increasing consumption of personal consumer electronic devices and the advancement of wearable electronics promote the rapid development of high-performance energy storage devices. As a new type of energy storage devices, supercapacitors have higher energy density and higher power density than traditional electrostatic capacitors. Compared with liquid electrolyte supercapacitors, solid-state supercapacitors integrate electrodes, solid electrolytes and separators into a whole, which have the advantages of light quality, easy to package, high safety, good flexibility and so on. Paper based electronic devices have great research and application prospects because of their low cost, flexibility, friendly environment, easy integration and so on. Paper is made up of cellulose fibers about 20m in diameter. These cellulose fibers contain many microfibers composed of dozens of nanometers in diameter, which make the paper have rough and porous surface. This kind of rough porous surface is a natural advantage for supercapacitors, which is advantageous to the adhesion of electrochemical active materials to the surface of cellulose. Conductive polymers such as polypyrrole (PPy), Polyaniline (PANI) are a class of conductive polymer materials with unique structure and excellent physical and chemical properties, easy to synthesize, high electrochemical activity, good electrical conductivity and low cost. The electrode suitable for supercapacitor has become a new hotspot in the research of supercapacitor in recent years. In this paper, the preparation of polymer-based paper-based flexible supercapacitor electrode materials and the assembly of devices are studied in detail. Graphite / PANI composite flexible electrode was prepared by pencil coating conductive graphite and electrodeposition, and PPy/Paper composite flexible electrode was prepared by "soaking polymerization method". Both methods are feasible. It can be widely used in the preparation of electrodes in other material systems. The electrochemical properties of the composite electrode were investigated by cyclic voltammetry, constant current charge-discharge and electrochemical impedance spectroscopy. The main conclusions are summarized as follows: 1. A thin layer of graphite was deposited on the common printing paper by the pencil coating process, and graphite conductive paper was prepared. The three-dimensional porous graphite / PANI flexible composite paper electrode was prepared by electrodeposition of PANI, on the graphite surface. The electrochemical performance of the electrode and its application in supercapacitor were systematically studied. The results show that the electrode has a stable chemical property with a square resistance of only 32.3 / sq.The surface capacitance of the electrode can reach 355.6 MV / cm ~ 2 at current density 0.5mA/cm2. The weight of the symmetric flexible solid supercapacitor assembled by graphite / PANI paper electrode is only 30.8 mg, and the bulk capacitance is 3.55 F / cm 3 at the volume current density 4.57mA/cm3, and at the power density 0.054W/cm3. The energy density is 0.32 mWh-cm3. After charging and discharging 10, 000 cycles, the capacitance remains 833. 2. The paper electrode coated with polypyrrole was prepared by soaking and polymerization. The PPy/Paper composite electrode has excellent electrical properties, the square resistance is as low as 4.5 / sq. the conductivity is 15s / cm, and the electrode is flexible and can bend 180 掳. And the electrical and electrochemical properties are almost unchanged. The flexible solid-state supercapacitors with sandwich structure and planar interDigital structure were assembled as electrodes, and the electrochemical properties of the corresponding solid-state devices were studied. The surface capacitance of solid state supercapacitor with flexible sandwich structure is 0.42F / cm ~ 2, and the energy density can reach 1mWh/ cm ~ (-3) at 0.27W/cm3 power density, which reveals its great application value in flexible energy storage field.
【学位授予单位】：武汉理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TQ317;TM53

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