电化学聚合制备基于导电聚合物的高能量密度超级电容器电极与器件

发布时间：2018-05-17 03:13

本文选题：超级电容器 + 导电聚合物　；参考：《吉林大学》2017年博士论文

【摘要】：从上世纪50年代见报于专利,到现在应用到全世界多个国家和地区的公共交通设施,短短几十年间,超级电容器经历了迅猛蓬勃的发展。随着近年来新能源汽车以及智能电子设备的普及,超级电容器有了更加广阔的发展空间。作为一种桥接普通电容器和蓄电池的电子器件,超级电容器具有介于上述两者之间的能量密度和功率密度。其用途广泛,可以在车辆制动过程中回收能量,并将其释放用于车辆加速;在启停系统中提供启动电源和稳定电压,为关键汽车应用提供后备电源和峰值功率;在智能电网系统中,削峰填谷,提升电网的可靠性和稳定性。超级电容器已经成为了很多领域重要的能源想选择方案。随着人们对其需求日益提升,超级电容器较低的能量密度成为其进一步发展的阻碍。目前商用的超级电容器主要采用碳基材料,其能量密度不超过10 Wh kg-1。导电聚合物由于储存电荷密度高、成本低廉、易于加工且兼具柔性等优点,被认为是非常有应用前景的一类超级电容器电极材料。但是,基于导电聚合物的超级电容器饱受功率密度低以及循环不稳定等问题的困扰。另外,其储存的能量密度取决于掺杂水平的高低,而常见的导电聚合物的掺杂度一般在为0.3-0.5之间,过高的掺杂度引起材料的不稳定从而导致能量密度无法进一步提升。在此背景下,我们从电极材料的合成以及新型电解质的设计角度出发,旨在通过简单有效的手段,在不牺牲功率密度的前提下,提升导电聚合物基超级电容器的能量密度,并寻求解决循环不稳定问题的途径。1、在第二章中我们制备了两种新型共轭微孔聚合物的电化学聚合薄膜,并首次用作赝电容的电极材料。这些薄膜电极材料的独特性在于,它们兼具共轭聚合物的优良导电性和微孔聚合物的丰富孔结构。这些特点在其超级电容性能上得到很好的展示:基于聚zn-mtcpp的赝电容电极材料的比电容值为142fg-1,基于聚bthcz的赝电容电极材料的比电容值为246fg-1,这些数值在文献报道的纯导电聚合物基电极材料中属于较高水平。得益于其高度交联的网络骨架和丰富的孔道,离子在电极材料表面可以快速地传输,使得两电极材料在高电流密度下均表现出良好的倍率稳定性,其中聚bthcz薄膜电极在100ag-1的高电流密度,仍然保持了93%的最大比电容。实验结果证明,电化学聚合新型的共轭微孔聚合物薄膜,为超级电容器提供了除传统导电聚合物如聚苯胺、聚吡咯和聚噻吩以外更多的电极材料选择。鉴于其结构的多样性和设计的灵活性,更多的共轭微孔聚合物薄膜电极材料会被开发出来,进一步加深我们对导电聚合物以及超级电容器的认识。2、在第三章中我们设计制备了两种具有不同连接方式的d-a构型的双极性掺杂导电聚合物电极材料,并深入研究了结构对其聚合行为、掺杂行为以及超级电容性能的影响。pczaqcz与paq3cz两电极材料制备的原型超级电容器器件的最大电压分别达到2.4v和2v。宽的电位窗口带来器件能量密度和功率密度的大幅提升,其中paq3cz器件的最大能量密度为19.5whkg-1(功率密度为1.2kwkg-1),最大功率密度为12.2kwkg-1(能量密度为16.4whkg-1);pczaqcz器件的最大能量密度为29.1whkg-1(功率密度为1.3kwkg-1),最大功率密度为11.8kwkg-1,(能量密度为23.3whkg-1),远高于商用的超级电容器的数值水平,体现了双极性掺杂材料的优越性。同时,我们深入探讨了影响iii类超级电容器循环稳定性的电荷捕陷效应。结果表明,循环充放电实验过程中,n掺杂电极严重的电荷捕陷效应是造成电极材料以及器件衰退的主要原因。paq3cz由于具有拓展的共轭结构,以及疏松的表面结构,有效地降低了n掺杂时的电荷捕陷效应,表现了优良的循环稳定性。另外,电荷捕陷效应导致的n掺杂活性的衰退被证明可以通过有限次数循环伏安扫描得到部分或几乎全部恢复,从而一定程度上延长器件的使用寿命。3、在第四章中我们首次探索了两种可用于有机电解液的氧化还原介质Fc和4-oxo TEMPO,两者具有非常快速可逆的氧化还原反应。在此基础上,我们制备了柔性的有机凝胶电解质和全固态超级电容器器件。受益于有机凝胶电解质的宽电压和氧化还原介质额外的法拉第电容,PEDOT作为电极材料的超级电容器的工作电压拓宽到1.5 V,比电容最高达到363 F g-1,能量密度达到27.4 Wh kg-1。证明在电解质中添加氧化还原介质是一种简单、普适、高效地提升超级电容器比电容以及能量密度的手段。在提升能量密度的同时,这些氧化还原介质还通过与PEDOT电极材料的协同作用,显著提高了超级电容器充放电循环稳定性。此外,两种具有氧化还原活性的有机凝胶电解质还可应用于基于其他电极材料如碳系、金属氧化物和其他导电聚合物的柔性、全固态超级电容器器件。同时,更多的可以用于有机电解液的氧化还原介质还有待被开发探索。综合有机电解液的宽窗口优势和氧化还原介质丰富的法拉第电容优势,超级电容器的能量密度有望得到大幅提升,甚至可以与电池相媲美。综上所述,在本论文中我们通过引入丰富的孔结构以及功能化的氧化还原基团,设计合成了新型的导电聚合物电极材料;制备了柔性的全固态超级电容器器件,又制备了具有氧化还原活性的有机凝胶电解质。这些对电极材料以及电解质的改性和修饰,有效地提高的电极材料的比电容,提升了器件的能量密度和功率密度。此外通过结构和性质的对比,我们深入分析了材料结构对其电容性能的影响,对认识导电聚合物的储能过程和机理、拓展适用的材料体系起到了积极的促进作用。
[Abstract]:Since the 50s last century, it was reported to the patent, and is now applied to public transportation facilities in many countries and regions all over the world. In the past few decades, the supercapacitor has experienced rapid and vigorous development. With the popularity of new energy vehicles and intelligent electronic equipment in recent years, the supercapacitor has a wider space for development. As a bridge, it is a bridge. An electronic device connected to a common capacitor and battery. The supercapacitor has an energy density and a power density between the two. It is widely used to recover energy during vehicle braking and release it for vehicle acceleration. The power supply and stable voltage are provided in the start and stop system, and it is provided for key automotive applications. Power supply and peak power; in smart grid systems, peaking and filling the valley to improve the reliability and stability of the power grid. Supercapacitor has become an important energy choice in many fields. With the increasing demand for it, the lower energy density of supercapacitor has become a hindrance to its further development. Carbon based materials are mainly used in stage capacitors. Their energy density is not more than 10 Wh kg-1. conductive polymers. Due to the advantages of high storage charge density, low cost, easy processing and flexibility, it is considered a very promising type of supercapacitor electrode material. However, the supercapacitor based on conductive polymer is full of power density. In addition, the energy density of the storage depends on the level of doping, and the doping degree of the common conductive polymers is generally between 0.3-0.5, the high doping degree causes the instability of the material and the energy density can not be promoted. In this context, we are from the electrode material. The synthesis and the design of new electrolytes are designed to improve the energy density of the conductive polymer based supercapacitor without sacrificing the power density, and to find a way to solve the cyclic instability problem,.1. In the second chapter, we have prepared two new conjugated microporous polymers in the second chapter. Polymeric films are used for the first time as electrode materials for pseudapacitor. The uniqueness of these thin film electrode materials is that they have both excellent conductivity of the conjugated polymer and the rich pore structure of microporous polymers. These characteristics are well displayed on its supercapacitor performance: the specific capacitance value of the pseudacapacitor electrode based on zn-mtcpp is 1 42fg-1, the specific capacitance value of the pseudopotential electrode material based on the poly bthcz is 246fg-1. These values are high in the pure conductive polymer base electrode materials reported in the literature. Thanks to the highly crosslinked network skeleton and rich channels, the ions can be quickly transmitted on the surface of the electrode material, making the two electrode material high current density. Under the high current density of the poly bthcz film electrode at the high current density of 100ag-1, the maximum specific capacitance remains 93%. The experimental results show that the electrochemical polymerization of the new conjugated microporous polymer film provides the supercapacitor except for the traditional conductive polymer, such as polyaniline, polypyrrole and polythiophene. More electrode materials are selected. In view of its structural diversity and design flexibility, more conjugated microporous polymer film electrode materials will be developed to further deepen our understanding of conducting polymers and supercapacitors. In the third chapter, we have designed and prepared two types of D-A configurations with different connection modes. Bipolar doped conductive polymer electrode material, and in-depth study of the structure of its polymerization behavior, doping behavior and the performance of supercapacitor properties of.Pczaqcz and paq3cz two electrode materials made of the prototype supercapacitor devices with the maximum voltage of 2.4V and 2V. wide potential window to bring the large energy density and power density of the device Amplitude enhancement, the maximum energy density of paq3cz device is 19.5whkg-1 (power density 1.2kwkg-1), the maximum power density is 12.2kwkg-1 (energy density 16.4whkg-1), the maximum energy density of pczaqcz device is 29.1whkg-1 (power density 1.3kwkg-1), the maximum power density is 11.8kwkg-1, (the energy density is 23.3whkg-1), far higher than that of the commercial device. The numerical level of the supercapacitor shows the superiority of the bipolar doped material. At the same time, we deeply investigate the charge trap effect on the cycle stability of the III type supercapacitor. The result shows that the serious charge trap effect of the N doped electrode is the main cause of the decay of the electrode material and the device during the cycle charge and discharge experiment. Due to the extended conjugate structure and loose surface structure,.Paq3cz effectively reduces the charge trap effect of N doping and exhibits excellent cyclic stability. In addition, the decline of the N doping activity caused by the charge trap effect is proved to be partially or almost completely restored by the finite number of cyclic voltammetry. To a certain extent, the service life of the device was extended to a certain extent.3. In the fourth chapter, we first explored two redox mediators of organic electrolyte, Fc and 4-oxo TEMPO, which have a very fast reversible redox reaction. On this basis, we have prepared a flexible organic gel electrolyte and all solid state supercapacitor. Benefiting from the wide voltage of the organic gel electrolyte and the extra Faraday capacitance in the oxidation-reduction medium, the working voltage of the supercapacitor as the electrode material is widened to 1.5 V, the maximum ratio of the specific capacitance reaches 363 F g-1, the energy density is 27.4 Wh kg-1., which proves that the addition of redox medium in the electrolyte is simple, universal and high. In addition to the increase of the energy density, these redox mediators also significantly enhance the charging and discharging cycle stability of the supercapacitor by synergistic action with the PEDOT electrode material. In addition, two organogels with oxidizing activity can also be applied to the base. In other electrode materials such as carbon, metal oxide and other conductive polymers, all solid state supercapacitor devices. At the same time, more oxidation-reduction media that can be used in organic electrolytes are still to be explored. Comprehensive organic electrolyte wide window advantages and rich Faraday capacitance advantages of oxidation-reduction medium, super The energy density of the capacitor is expected to be greatly improved and even comparable to that of the battery. In this paper, in this paper, a new type of conductive polymer electrode material is designed and synthesized by introducing a rich pore structure and functional redox groups. Organic gel electrolytes with redox activity. These electrode materials and electrolytes are modified and modified, the specific capacitance of the electrode materials is improved effectively, and the energy density and power density of the devices are enhanced. Furthermore, through the comparison of the structure and properties, we have deeply analyzed the effect of the material structure on its capacitive performance. The energy storage process and mechanism of conductive polymers play a positive role in expanding the applicable material system.
【学位授予单位】：吉林大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：O631;TM53

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