金属氧化物与碳纳米管复合电极材料用于超级电容器

发布时间：2018-02-04 08:49

  本文关键词： 超级电容器 氧化镍 碳纳米管 比电容 电化学性能　出处：《吉林大学》2017年硕士论文　论文类型：学位论文

【摘要】：超级电容器是一种具有较高能量密度和功率密度的储能设备,主要应用在混合动力汽车、移动电子设备等领域中,是一种新型储能设备。超级电容器组成结构主要包括以下几部分:电极材料和隔膜以及电解液,其中电极材料是用来作为超级电容器的核心组成部分,成为目前研究的热点。本文主要选用碳基材料和金属氧化物的复合物作为电极材料,主要是因为金属氧化物具有较大的理论比电容,以便储存能量,但由于其导电性能较差,循环性能不好,从而造成不能够达到其相应的比电容;而碳基材料(碳纳米管)具有优良的导电性,大的比表面积,可以有效改善金属氧化物上述缺点,故将两种材料进行复合,集合两种材料的优点。本实验是运用水热法将两种材料进行复合,合成一种电化学性能优良复合电极材料,具体实验如下:1.采用水热法,通过控制水热温度,进而可以合成形貌的不同电极材料。具体是在碱性条件下通过简单的水热法制备了纳米结构的NiO\CNTs复合材料,氧化镍纳米片在复合材料中主要是为碳纳米管附着提供了基底作用,通过对样品的形貌和结构进行表征发现碳纳米管通过范德瓦尔力或者π-π键可以成功的附着在NiO纳米花的表面上。此外,制备的不同水热温度下复合材料通过进行电化学性能测试,采用6 M KOH为电解液,三电极体系下进行测试的,通过恒流充放电测试发现NC-15(水热温度在150℃)的比电容在电流密度为5 A g-1时可达2171 F g-1,进行1000次循环伏安曲线测试后,NC-15复合材料的容量保留率为92.8%,通过实验得出复合材料具有优异的电化学性能,说明氧化镍和碳纳米管复合材料是一种有前景的超级电容器电极材料。2.通过一步水热法,合成NiO和CNTs不同质量比的复合电极材料。加入不同量CNTs,合成的复合电极材料通X射线衍射(XRD)、扫面电子显微镜(SEM)及等温氮吸附-脱附(BET)等一系列表征发现,只有在NiO:CNTs=1:1时,具有最好结晶度,最好的形貌,最大的比表面积。然后通过三电极系统进行电化学测试,结果NC11具有最好的电化学性能。综上,本文合成的复合材料合成过程简单以实现形貌各异、电化学性能优秀的超级电容器电极材料。
[Abstract]:Supercapacitor is a kind of energy storage equipment with high energy density and power density, which is mainly used in hybrid electric vehicle, mobile electronic equipment and other fields. Supercapacitor is a new type of energy storage equipment. The structure of supercapacitor consists of the following parts: electrode material, diaphragm and electrolyte, among which electrode material is used as the core component of supercapacitor. In this paper, the composite of carbon-based materials and metal oxides is chosen as electrode material, mainly because metal oxides have large theoretical capacitance to store energy. However, due to its poor conductivity and poor cycle performance, it can not reach its corresponding specific capacitance. Carbon based materials (carbon nanotubes) have good electrical conductivity, large specific surface area, can effectively improve the shortcomings of metal oxides, so the two materials are combined. This experiment uses hydrothermal method to compound the two materials to synthesize a kind of composite electrode material with excellent electrochemical performance. The specific experiments are as follows: 1. Hydrothermal method is adopted. Different electrode materials with different morphologies can be synthesized by controlling hydrothermal temperature. In particular, nanostructured NiO\ CNTs composites were prepared by simple hydrothermal method under alkaline conditions. Nickel oxide nanoparticles provide the substrate for the adhesion of carbon nanotubes in the composites. Through the characterization of the morphology and structure of the sample, it was found that the carbon nanotubes could be successfully attached to the surface of the NiO nano-flowers by Van der Waldley or 蟺-蟺 bond. The electrochemical properties of the composites prepared at different hydrothermal temperatures were tested using 6 M KOH as electrolyte and three-electrode system. The constant current charge-discharge test shows that the specific capacitance of NC-15 (hydrothermal temperature is 150 鈩，

本文编号：1489848