金属基原位生长薄膜电极材料的制备及电化学性能研究

发布时间：2019-01-08 19:00

【摘要】：随着当代社会的高速发展，能源材料已经越来越重要，学者们将大量的注意力放在可以快速充放电且储能量超高、性质稳定的材料研究上。电化学储能材料在近些年来研究最为广泛，从最初的镍-镉电池发展到优化储电性能的锂离子电池直到如今的充电时间短且使用寿命长的电化学电容器，也称为超级电容器。这类电容器由三大类材料组成：碳材料、导电聚合物材料以及金属氧化物/硫化物材料。根据不同材料所具备的物理化学性质不同，所组成的电极材料的能量密度、循环寿命等性质也有所不同。目前已有许多超级电容器材料应用在电动汽车、智能设备、电力系统以及太阳能产品等日常生活领域。从储能机理上可以将超级电容器分为两种，前一个由活性炭材料、碳纤维、碳纳米管等碳材料电极组成的电容器称为双电层电容器，而后一由金属氧化物和聚合物电极材料组成的电容器称为法拉第赝电容器。在本论文中我们对两种类型的电容器都进行了研究，所制备的四种电极材料分别有泡沫钛基PPy电极材料、泡沫镍基PPy/Ag复合电极材料、泡沫镍基C薄膜电极材料以及铜箔基CuS电极材料，我们所制备的四种电极材料特点都是在不添加任何黏合剂的情况下，利用原位生长法在金属基底上制备出导电的纳微米薄膜材料，整个过程不会引入其它杂质。经过扫描电子显微镜（SEM）、透射电子显微镜（TEM）、X射线粉末衍射仪（XRD）、紫外可见光谱仪（UV）以及红外可见光谱仪（FTIR）这些仪器对电极材料的表面进行形貌的表征和组分的分析，并利用电化学工作站的循环伏安法（CV）、恒电流充放电法（GCD）以及循环寿命测试对电极的电化学性质进行表征，文中我们详细对比了不同时间、不同浓度下制备的电极材料的形貌与电化学性能，通过讨论得到性质最优的电极材料。比如生长时间为12h的泡沫钛基PPy电极在电流密度为1A g-1时比电容高达855F g-1；反应时间为7h的泡沫镍基PPy/Ag电极在1Ag-1时比电容为493Fg-1；利用葡萄糖水热法原位合成的C修饰泡沫镍电极的电容性能和循环寿命较同类型的碳材料要高很多；反应时间为18h的0.1mol L-1CuSO4和Na2S2O3溶液中制备的铜箔基CuS薄膜电极的比电容值高达1093F g-1（1Ag-1）。作为主要的制备手段，，原位生长法是本论文的特点，简单的操作环境和方便的制备过程是超级电容器领域新的发展方向。
[Abstract]:With the rapid development of modern society, energy materials have become more and more important. Scholars have paid a lot of attention to the research of materials which can charge and discharge rapidly and have super high energy storage and stable properties. Electrochemical energy storage materials have been widely studied in recent years, from the initial Ni-CD battery to the lithium ion battery with optimized storage performance to electrochemical capacitors with short charging time and long service life, also known as supercapacitors. These capacitors consist of three main types of materials: carbon materials, conductive polymer materials, and metal oxide / sulfide materials. According to the physical and chemical properties of different materials, the energy density and cycle life of the electrode materials are different. At present, many supercapacitor materials have been used in electric vehicles, smart devices, power systems, solar products and other areas of daily life. In terms of energy storage mechanism, supercapacitors can be divided into two types. The former capacitor composed of activated carbon materials, carbon fibers, carbon nanotubes and other carbon material electrodes is called double layer capacitors. Then a capacitor composed of metal oxide and polymer electrode material is called Faraday pseudo-capacitor. In this thesis, we studied two types of capacitors. The four kinds of electrode materials are titanium foam PPy electrode material, nickel foam PPy/Ag composite electrode material. Foamed nickel based C thin film electrode materials and copper foil based CuS electrode materials, the four kinds of electrode materials we prepared are all characterized by the addition of no binder. In situ growth method was used to fabricate conductive nanometer-thin films on metal substrates without introducing other impurities in the whole process. Scanning electron microscope (SEM), transmission electron microscope (TEM), X ray powder diffractometer (XRD), Ultraviolet visible spectrometer (UV) and infrared visible spectrometer (FTIR) were used to characterize the surface morphology of electrode materials and analyze their components. The electrochemical workstation was used for cyclic voltammetry (CV),). The electrochemical properties of the electrode were characterized by constant current charge-discharge method (GCD) and cyclic life test. In this paper, the morphology and electrochemical properties of the electrode materials prepared at different time and different concentration were compared in detail. The optimal electrode material is obtained by discussion. For example, when the current density is 1A g ~ (-1), the specific capacitance of foamed titanium based PPy electrode is up to 855 F g ~ (-1), and the specific capacitance of foamed nickel based PPy/Ag electrode with 7 h reaction time is 493Fg-1 at 1Ag-1, when the current density is 1A g ~ (-1). The capacitance and cycle life of C-modified nickel foam electrode prepared by in-situ synthesis of glucose hydrothermal method are much higher than those of the same type of carbon materials. The specific capacitance of copper foil based CuS thin film electrode prepared in the solution of 0.1mol L-1CuSO4 and Na2S2O3 for 18 h was 1093 F g ~ (-1) (1Ag-1). As the main preparation method, in situ growth method is the characteristic of this paper. The simple operating environment and convenient preparation process are the new development direction in the field of supercapacitor.
【学位授予单位】：吉林大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：O646;TB383.2

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