Preparation And Electrochemical Performance Of Carbon Based On Hybrid Supercapacitor Material

With high power density, long cycle life, fast charging and discharging speed, the super-capacitor is a new energy between batteries and traditional capacitor storage device, which is widely used in all kinds of electric systems at present and has received great attention in the global scope. As the core of the supercapacitor, electrode materials received much attention. Activated carbon electrode material, nickel oxide, nickel oxide graphite composite electrode materials were made in different ways by optimizing process preparation. Besides, the material preparation, characterization, the electrochemical properties were studied systematically and the asymmetric capacitor assembly was tested in electrochemistry. The main research contents of this paper are following:(1) Taking Xinjiang Kuche coal as raw material, we replace KOH as activator with Ca(OH)2in different proportion. In N2tube furnace, different temperatures activate activated carbon at different alkali and different temperatures; The products were characterized by XRD, SEM and BET. Through the cyclic voltammograms, charge-discharge and impedance, activated carbon gets the electrochemical test to choose the preparation conditions of activation activated carbon with better electrochemical properties.(2) NiO was prepared with Nickel sulfate and hexamethylenetetramine of different mole ratio under the condition of hydrothermal, and TG, XRD, SEM, TEM, BET are used for its material characterization test.Nickel sulfate and hexamethylene amine1:3are made into NiO, which has the good layered spheres and bimodal aperture structure, different proportions of NiO materials are conducted to voltampere test, charge-discharge test and impedance test. NiO materials made from Nickel sulfate and hexamethyleneamine1:3in6M KOH electrolyte and exhibits a high specific discharge capacitance of1022F·g-1at0.5A·g-1, In addition, the capacitance keeps at least about88%after1000cycles. (3) NiO/GNS/GC composite has been synthesized with glucose, nickel sulfate and graphite oxide as raw materials through the hydro thermal. In the hydrothermal process, Glucose can not only be used as a reducing agent reductive graphite oxide, but also plays an important role in the cambium like composite structure. And XRD, Raman, IR, SEM, HRTEM, BET were used to characterize the structure of material performance and CV, CP tested the electrochemical performance. Composite materials shows a specific discharge capacitance of1495F·g-1at0.5A·g-1in6M KOH electrolyte. In addition, the capacitance keeps at least about90%after1000cycles(4) Asymmetric supercapacitor was assembled by using optimized nickel oxide as anode material and activated carbon as anode materials.The positive and negative material are systematically characterized by XRD, SEM and BET. Moreover, the electrochemical performance of material was evaluated by CV and GCD. Electrochemically tests show that from three electrode system to the actual application of asymmetric supercapacitor, potential window increased to1.4V due to the synergy of nickel oxide and activated carbon. Furthermore, the cycling test results showed that material exhibited cycling stability with only7%decay after1000cycles.