超级电容器电极材料的化学合成及其性能研究

发布时间：2018-01-11 18:06

本文关键词：超级电容器电极材料的化学合成及其性能研究　出处：《安徽师范大学》2014年硕士论文　论文类型：学位论文

【摘要】：为了应对日益严重的能源危机和环境问题，发展清洁的具有高功率密度和低消耗的可持续能源已经迫在眉睫。近年来，超级电容器（又叫电化学电容器）由于其高的功率密度、长的使用寿命和低消耗等特点而受到人们广泛的关注，并在不间断功率器件、混合点动力车和可再生能源等许多领域展示出巨大的潜在应用价值。一般而言，超级电容器可以根据其储能机理分为两大类：双电层电容器和赝电容电容器。决定超级电容器性能的最关键因素就是电极材料的选择，所以开发出适当的电极材料，可以增大超级电容器的电容量。本论文研究了多种电极材料的化学制备，并对其电化学储能性能进行了测试，主要内容如下： 1、采用控制水热条件（反应时间，温度），以不同镍源，钴源和碱性物质为原料，制备出四种不同形貌的钴酸镍纳米结构：纳米丝、六角星、六棱柱和六角片，通过X-射线粉末衍射，X-射线光电子能谱，热重分析，扫描电镜和透射电镜等多种手段对产物进行表征；结合氮气的吸附解吸测试和电化学性能测试，探索产物的比表面积和孔径分布对材料电容性能的影响。 2、采用两步的水热反应，以钴和镍的氢氧化物作为牺牲模板，成功制备出直径为200纳米，厚度约50纳米，壁厚10纳米的NiCo2S4中空六角片纳米结构，并利用X-射线粉末衍射，X-射线光电子能谱，X射线能量散射谱和扫描电镜以及透射电镜等对产物进行表征，并对产物的比电容进行了测试。 3、利用废弃生物质材料—莲蓬为原材料，在不同的温度下直接碳化制备出多孔碳材料，产物经X-射线粉末衍射，X-射线光电子能谱，氮气的吸附解吸测试，扫描电镜以及透射电镜分析，研究发现在600°C下所制备的碳材料具有高达563.4m2g1的比表面积，孔径平均为2.2纳米，作为超级电容器电极材料时测得电容为165Fg1，并表现出优越的稳定性能。 4、利用柯肯达尔效应，首次在泡沫镍基底上制备出截面为六边形的Co9S8纳米管阵列，产物通过X-射线粉末衍射，X-射线光电子能谱表征其组成，由扫描电子显微镜以及透射电子显微镜观察，其管径约为120200nm，纳米管壁厚约为40 60nm。作为超级电容器的电极，测得其比电容为1775Fg1，2000次充放电循环后任然保留最初容量的91.4%。 5、在泡沫镍基底上水热生长出相互交织的Co-Ni双氢氧化物（LDHs）纳米片阵列，产物通过X-射线粉末衍射，X-射线光电子能谱，扫描电子显微镜和透射电子显微镜表征，纳米片的厚度约为20纳米，，当直接用作超级电容器电极时，比电容高达1735Fg1。
[Abstract]:In order to deal with the increasingly serious energy crisis and environmental problems, it is urgent to develop clean and sustainable energy with high power density and low consumption. Because of its high power density, long service life and low consumption, supercapacitors (also called electrochemical capacitors) have attracted wide attention, and have been widely used in uninterrupted power devices. Many areas, such as hybrid point cars and renewable energy, have shown great potential applications. In general, supercapacitors can be classified into two main categories according to their energy storage mechanisms:. Double layer capacitors and pseudo capacitor capacitors. The choice of electrode material is the most important factor to determine the performance of supercapacitor, so the appropriate electrode material is developed. In this paper, the chemical preparation of various electrode materials is studied, and its electrochemical energy storage performance is tested. The main contents are as follows: 1. Four kinds of nickel cobalt nanostructures with different morphologies were prepared by controlling hydrothermal conditions (reaction time, temperature, nickel source, cobalt source and alkaline material): nanowires, hexagonal star. The products were characterized by X ray powder diffraction X ray photoelectron spectroscopy thermogravimetric analysis scanning electron microscope and transmission electron microscope. The effects of the specific surface area and pore size distribution of the product on the capacitive properties of the materials were investigated by combining the adsorption and desorption tests of nitrogen and electrochemical performance tests. 2. By using two-step hydrothermal reaction and cobalt and nickel hydroxides as sacrificial templates, 200 nanometers in diameter and about 50 nanometers in thickness were successfully prepared. NiCo2S4 hollow hexagonal nanostructures with a wall thickness of 10 nm were obtained by X-ray powder diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). X-ray energy scattering spectra, scanning electron microscopy and transmission electron microscopy were used to characterize the product, and the specific capacitance of the product was measured. (3) porous carbon materials were prepared by carbonization at different temperatures using waste biomass material Lianpeng as raw material, and the products were analyzed by X-ray powder diffraction (X- ray) and X-ray photoelectron spectroscopy (XPS). The adsorption and desorption tests of nitrogen, SEM and TEM analysis show that the carbon materials prepared at 600 掳C have a specific surface area of 563.4m2g1. The average pore size is 2.2 nm. The capacitance measured as electrode material of supercapacitor is 165 Fg1, and it shows excellent stability. (4) Co9S8 nanotube arrays with hexagonal cross section were prepared on nickel foam substrate by Kokendal effect for the first time. The products were characterized by X-ray photoelectron spectroscopy (XPS). The scanning electron microscope and transmission electron microscope show that the diameter of the tube is about 120200 nm and the wall thickness of the nanotube is about 40 掳60nm. it is used as the electrode of supercapacitor. Its specific capacitance is 1 775 FG 1 / 2 000 charge / discharge cycles and 91.4% of the original capacity is retained. 5. Interlaced Co-Ni double hydroxide (Co-Ni) nanocrystalline arrays were grown by hydrothermal method on nickel foam substrates. The products were diffracted by X-ray powder diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed that the thickness of the nanocrystalline was about 20 nm, and the specific capacitance was 1735 Fg1 when it was directly used as a supercapacitor electrode.
【学位授予单位】：安徽师范大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM53

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