过渡金属氧化物电极材料的制备及其超级电容性能的研究

发布时间：2018-03-21 17:31

本文选题：超级电容器　切入点：电极材料　出处：《兰州理工大学》2014年硕士论文　论文类型：学位论文

【摘要】：超级电容器是性能介于传统电容器和电池之间的一种新型储能装置,电极材料是超级电容器研究的核心组成部分。Co、Ni等过渡金属氧化物由于具有较高的比电容和能量密度且价格低廉、容易制备,近年来已成为超级电容器电极材料的研究热点。在实际应用中,Co、Ni等过渡金属氧化物的微纳米结构如晶粒大小、晶体形貌是影响和决定其电化学性能的关键参数。本论文采用液相沉淀法分别制备了C0304和Co3O4-NiO复合氧化物纳米材料,利用相关的分析测试手段对材料的晶型结构、形貌等进行了表征,对Co、Ni等过渡金属氧化物构成的电极材料进行了循环伏安、恒流充放电及交流阻抗等电化学性能测试,此外,对Co2+掺杂聚苯胺复合薄膜的耐腐蚀性能进行了初步研究。主要研究内容如下： (1)采用简单的液相沉淀法制备前驱体,经煅烧得到无定形具有疏松片状结构的纳米C0304电极材料。研究了晶型导向剂、反应时间及反应温度等因素对C0304电极材料的电化学性能的影响。结果表明,以[Na2(PO3)]6为晶型导向剂制备的C0304纳米材料,在电流密度为5mA·cm-2下放电比电容为851.67F·g-1,在常温下经过250次循环充放电后的比电容衰减率为10.05%,表现出良好的电化学稳定特性。 (2)以钴盐与镍盐为原料,用水-乙醇混合溶液作为反应溶剂,采用液相沉淀法一步合成复合氧化物前驱体,经焙烧后得到Co3O4-NiO纳米复合氧化物。考察了钴与镍的摩尔比、溶剂体积比、前驱体热处理温度以及表面活性剂等因素对复合氧化物电极材料微观形貌和比电容的影响。结果表明,当钴与镍的摩尔比为(1：1),水与乙醇体积比为(1：2)时,在电流密度为2mA·cm-2下的恒流充放电测试,得到复合物电极材料的比电容为1832F·g-,并且常温下经过1000次循环充放电之后其比电容衰减率仅为1.863%, Co3O4-NiO复合氧化物表现出优异的电化学性能和良好的循环稳定性。 (3)以Co2+作为掺杂剂,电化学合成Co2+掺杂聚苯胺(PANI/Co2+)复合薄膜,利用FT-IR、XRD等测试手段对其结构进行表征。研究了Co2+对循环伏安电合成聚苯胺膜的影响和PANI/Co2+复合薄膜的耐腐蚀性能。结果表明,Co2+的掺杂浓度会影口PANI膜的耐腐蚀性,PANI/Co2+复合薄膜的腐蚀电位相对于单纯的PANI薄膜的腐蚀电位发生明显的正移且腐蚀电流密度显著降低,表现出较好的耐腐蚀性。
[Abstract]:Supercapacitors are a new type of energy storage device whose performance is between conventional capacitors and batteries. Electrode material is the core component of supercapacitor research. Because of its high specific capacitance and energy density and low price, transition metal oxides such as Cotinie are easy to be prepared. In recent years, it has become a hotspot in the research of electrode materials for supercapacitors. The crystal morphology is the key parameter to influence and determine the electrochemical performance. In this paper, C0304 and Co3O4-NiO composite oxide nanomaterials were prepared by liquid-phase precipitation method. The electrochemical properties of the electrode materials made of transition metal oxides such as Co-Ni were measured by cyclic voltammetry, constant current charge-discharge and AC impedance. The corrosion resistance of Co2 doped Polyaniline composite film was studied. The precursor was prepared by a simple liquid precipitation method, and the amorphous C0304 electrode material with loose flake structure was obtained by calcination. The effects of reaction time and reaction temperature on the electrochemical properties of C0304 electrode materials were studied. The results showed that the C0304 nanomaterials were prepared with [Na _ 2PO _ 3] _ 6 as crystal guide. At the current density of 5 Ma 路cm-2, the specific capacitance is 851.67 F 路g-1, and the attenuation rate of the specific capacitance after 250 cycles at room temperature is 10.05, showing good electrochemical stability. Using cobalt salt and nickel salt as raw materials and water-ethanol mixed solution as reaction solvent, composite oxide precursor was synthesized by liquid-phase precipitation method. After calcination, Co3O4-NiO nano-composite oxide was obtained. The molar ratio of cobalt to nickel was investigated. The effects of solvent volume ratio, precursor heat treatment temperature and surfactant on the micromorphology and specific capacitance of composite oxide electrode materials were investigated. The results show that the molar ratio of cobalt to nickel is 1: 1 / 1, and the volume ratio of water to ethanol is 1: 2). Constant current charge and discharge measurements at a current density of 2 Ma 路cm-2. The specific capacitance of the composite electrode material is 1832F g-and the specific capacitance attenuation rate of the composite electrode material is only 1.863 after 1000 cycles at room temperature. The Co3O4-NiO composite oxide exhibits excellent electrochemical performance and good cyclic stability. (3) Co2 doped Polyaniline / Pani / Co _ 2 composite films were synthesized by electrochemical synthesis with Co2 as dopant. The structure of Polyaniline film was characterized by FT-IR XRD. The effect of Co2 on the synthesis of Polyaniline film by cyclic voltammetry and the corrosion resistance of PANI/Co2 composite film were studied. The results show that the doping concentration of Co 2 will influence the corrosion resistance of PANI film. The corrosion potential of the composite film is obviously positive shift and the corrosion current density is significantly lower than that of the pure PANI film. Show good corrosion resistance.
【学位授予单位】：兰州理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：O646;TM53

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