Preparation Of Graphene And Research Of Supercapacitor Made By Graphene Composite Electrode

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.