Ni-Mn基复合材料的制备及其在超级电容器中性能研究

发布时间：2018-05-04 21:07

本文选题：Ni-MnLDH + Ni-MnLDO　；参考：《上海应用技术大学》2017年硕士论文

【摘要】：超级电容器因具有快速充放电、功率密度高、循环稳定性好等优点成为人们研究的热点,而其性能的好坏主要由电极材料决定,因此,研发性能优异的电极材料备受人们的关注。超级电容器工作电极主要由碳、金属氧化物/氢氧化物、导电聚合物以及他们的复合材料几类,其中碳材料具有较好的导电性、功率密度和循环稳定性,但其比容量较低;金属氧化物/氢氧化物具有较高的比容量,但功率密度较小,且导电性不好。此外,过渡金属氧化物/氢氧化物具有独特的二维柱状结构,同时具备双电层和赝电容两种性质的电容,但单一的过渡金属氧化物/氢氧化物能量密度较低,不能满足人们对电容器性能的要求。针对其缺陷,近年来人们努力研发其与碳、导电聚合物等物质的复合材料。本论文主要研究了过渡金属Ni-Mn LDH和Ni-Mn LDO的复合电极材料,具体研究内容如下:(1)以三维大孔网状结构的泡沫镍为基底,以廉价的葡萄糖为碳源,通过简单的两步水热法得到柔性LNC复合电极材料。LNC可以直接用作工作电极,不需要粘合剂和导电剂的加入。通过在三电极体系中测试发现,在0.5 A g-1的电流密度条件下,比容量达到1916Fg-1。将其组装成不对称电容器器件,在0.5 Ag-1的电流密度条件下,比容量达到121 F g-1,并且在5 A g-1的电流密度条件下充放电循环5000圈后,比容量仍然保持在84.3%,具有良好的循环稳定性和功率密度,这在实际应用中具有很大的意义。(2)通过简单的水热-碳化操作处理,得到三维石墨烯溶洞花球状Ni-Mn LDO复合材料(GL)。GL具有很好的阶层结构,在三电极体系中测试表明,在0.5 Ag-1的电流密度条件下,比容量达到1648 Fg-1,即使在大电流密度10 A g-1条件下比容量仍然可以达到1252 Fg-1,并且在循环充放电6000圈后,比容量保持率仍在96%,具有很好的循环稳定性,这在实际应用中具有重要的意义。在不对称电容器器件测试中,也具有很好的电化学性能。
[Abstract]:Supercapacitors with the advantages of rapid charge and discharge, high power density and good cycle stability have become the focus of research, and the performance of supercapacitors is mainly determined by electrode materials. The research and development of electrode materials with excellent performance has attracted people's attention. The working electrodes of supercapacitor are mainly composed of carbon, metal oxide / hydroxide, conductive polymer and their composite materials. The carbon materials have good electrical conductivity, power density and cyclic stability, but their specific capacity is low. Metal oxide / hydroxide has high specific capacity, but low power density and poor conductivity. In addition, transition metal oxide / hydroxide has a unique two-dimensional columnar structure, and a double layer and pseudo-capacitance capacitors, but a single transition metal oxide / hydroxide has a low energy density. It can not meet the requirements of capacitor performance. Due to its defects, people have been developing composites with carbon, conductive polymers and other materials in recent years. In this paper, the composite electrode materials of transition metal Ni-Mn LDH and Ni-Mn LDO are studied. The main contents are as follows: 1) the nickel foam with three dimensional macroporous network structure is used as the substrate, and the cheap glucose is used as the carbon source. The flexible LNC composite electrode material. LNC can be directly used as the working electrode by a simple two step hydrothermal method without the addition of binder and conductive agent. It was found that the specific capacity reached 1916 Fg-1 at the current density of 0.5 A g ~ (-1) in a three-electrode system. The device is assembled into an asymmetric capacitor. The specific capacity of the device is 121F g-1 at the current density of 0.5 Ag-1, and the charge / discharge cycle is 5000 cycles at the current density of 5 A g ~ (-1). The specific capacity remains at 84.3, with good cyclic stability and power density, which is of great significance in practical applications. Three dimensional graphene cavernous spherical Ni-Mn LDO composite (GLN. GL) has a good hierarchical structure. The results of three-electrode system show that at the current density of 0. 5 Ag-1, the structure of GLN / GL is very good. The specific capacity can reach 1648 Fg-1, even under the condition of high current density 10 A g ~ (-1), the specific capacity can still reach 1252 Fg-1, and the specific capacity retention rate is still 96% after the cycle charge and discharge of 6000 cycles, which has good cycle stability. This is of great significance in practical application. It also has good electrochemical performance in the measurement of asymmetric capacitor devices.
【学位授予单位】：上海应用技术大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB331;TM53

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