Preparation And Study Of Metal Doped Carbon Carbide, Oxide Graphene / V ₂ 5 Complex Supercapacitor Electrode Materials

The capacitor is commonly used in electronic devices to store charge. While with the rapid development of technology, the earlier circuit structure become more complex so that ordinary capacitor can no longer meet the needs of circuit operation. In order to achieve the needs of high load even overload circuit, scientists began to promote the use of supercapacitor device, which is much more superior to traditional capacitors. The key to the development of supercapacitor is the preparation of electrode materials. In this dissertation, we studied the preparation and characterization of metal-doped carbon xerogel electrode materials for electric double layer capacitor and the graphene oxide/V2O5composite electrode materials for pseudocapacitor. The details results are summarized as followed:1. We demonstrated a cost-effective sol-gel synthesis to prepare metal-doped carbon xerogel material with metal nitrates as a catalyst. In this method, metal nitrates played both the role of catalyst of sol-gel reaction and graphitization process of carbon gel. At a result, the degree of graphitization of generated carbon xerogel increased with the addition of metal ions and two-dimensional runnel-like structure formed, which is conducive to the transportation of electrolyte. The products were characterized by X-ray diffraction, Raman spectroscopy, thermogravimetric analysis, nitrogen adsorption-desorption experiment, cyclic voltammetry and constant current charge-discharge experiment. Moreover, long-term cycling behavior showed that prepared metal-doped carbon xerogel materials performed well in electrical double layer supercapacitor and there is great potential for practical application in the future.2. Based on hydrothermal method, we showed a one-step synthesis of graphene oxide/V2O5composite. In the method, the addition of a small amount of graphene oxide can be concluded into two aspects:increasing the conductive properties of V2O5and improving the hydrophilic properties of the composite with the oxygen-containing functional groups on its surface. The structure and composition of the nanocomposite has been characterized by scanning electron microscopy, X-ray diffraction, thermogravimetric analysis, Fourier transform infrared spectroscopy, nitrogen adsorption-desorption experiments, cyclic voltammetry and constant current charge-discharge test. The results of electrochemical tests showed that the composite prepared has excellent capacitive properties for the use of psedocapacitor. While the preparation method is simple and energy-efficient, the nanocomposite will have good potential applications in the future.