【作者】 周磊；

【导师】 何大伟；

【作者基本信息】 北京交通大学 ， 光学， 2015， 硕士

【摘要】 石墨烯(RGO)由于其独特的物理结构成为了理想的超级电容器电极材料。研究发现,石墨烯与其他纳米材料进行复合能够有效地弥补石墨烯的缺陷,提高超级电容器的性能。本文制备了纯RGO、RGO/CNTs二元复合材料、RGO/CNTs/MnO2三元复合材料,然后将他们作为超级电容器的电极,对超级电容器的性能展开研究。本文主要完成了以下几个方面的工作：(1)制备RGO,并将纯RGO作为超级电容器电极,通过循环伏安(CV)与恒流充放电(GCD)对纯RGO超级电容器进行测试,以此测试结果与复合材料的比电容进行对比。(2)采用原位复合法制备了RGO/CNTs二元复合材料,并对复合材料进行了TEM与SEM表征。然后研究了RGO与CNTs的质量比分别为4：1、3：1、2：1、1：1、1：2的复合电极对于超级电容器比电容的影响。通过对RGO/CNTs超级电容器进行循环伏安(CV)与恒流充放电(GCD)测试发现,当RGO:CNTs为1：1时,RGO/CNTs二元复合物的复合效果最好,相对于纯RGO电极来说有了较大的提高。(3)用简便的方法制备了RGO/CNTs/MnO2三元复合材料,并对复合材料进行了SEM与XRD表征。在RGO:CNTs为1：1的前提下,研究了Mn02百分含量分别为0%、10%、20%、30%、40%的复合电极对于超级电容器比电容的影响。通过对超级电容器进行电化学测试发现,随着Mn02含量逐渐增加,超级电容器的比电容也相应地增加,当Mn02的含量增加到30%时,超级电容器的比电容达到最大,与相同条件下的RGO/CNTs超级电容器的比电容相比有了一定的提高。更多还原

【Abstract】 RGO has become an ideal supercapacitor electrode material due to its unique physical structure. Research shows that synthesis of RGO and other nanomaterials can effectively compensate for deficiencies of pure RGO, and will improve the performance of supercapacitors. This article describes the preparations of pure RGO, RGO/CNTs composites, and RGO/CNTs/MnO2composites, and how to use them as supercapacitor electrodes. Investigations have been done on performance of these supercapacitors.Main works include:(1) By testing pure RGO supercapacitor with cyclic voltammetry (CV) and constant current charge and discharge (GCD), it is discovered that at a currency density of0.2A/g, the specific capacitance of which is112F/g. And this specific capacitance is used to compare with which of the composits electrode.(2) The article describes the preparation method of RGO/CNTs composites which are tested by TEM and SEM, and explores the effects of supercapacitors with different weight ratio of composite capacitance which is used as super capacitor electrodes. By testing supercapacitor with cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD), it is discovered that along with an increase in the percentage of carbon nanotube weight, supercapacitors correspondingly increase in capacitance. When weight of carbon nanotubes increases to RGO:CNTs of1:1, the specific capacitance of supercapacitor reaches the maximum, Which achieves a great increase compared with pure RGO supercapacitors in the uniform test condition.(3) This paper prepares for composites of RGO/CNTs/MnO2. In RGO:CNTs of1:1, the effects of different percentages of MnO2to supercapacitors capacitance are investigated. By electrochemical tests on supercapacitor, along with increases of MnO2, the specific capacitance of supercapacitors increases as well. When MnO2is increased to30%, capacitance reaches the maximum, Which achieves a increase compared with supercapacitors made with RGO/CNTs electrode. When MnO2is increased to40%, the capacitance decreases slightly, yet its rate performance is best.更多还原