| The super capacitor as a new energy storage device has been used in the field of electric vehicle, wind power and mobile communication systems. The flexibility of electronics has become an important development direction of mechanical products with the fast development of technology, therefore it is necessary to develop a capacitor has the qualities of flexibilityIt is well known that the electrode material plays an important role and cobalt, nickel fund belongs to the hydrogen(oxygen) compound because of its good redox reaction activity and has an excellent electrochemical performance with unique micro structure, in terms of electrode materials show the potential application value. And use the relevant test method on the morphology of the target material, crystal structure and composition are analyzed, such as characterization, electrochemical test and analysis on the material of the electrochemical properties of certain research. The main contents are as follows: 1. Using a cheap commercial graphite pulp as raw material, was prepared through the method of vacuum pump must be flexible graphite sheet. The graphite paper has good electrical conductivity and flexibility, and show the excellent performance of capacitance. The preparation provides a simple and effective new way to make an unsupported graphite base film 2. Cobalt fund belongs to the hydrogen(oxygen) compound preparation of nanomaterials and their electrochemical performance(a) First, we successfully electrodeposited interconnected Co(OH)2 nanosheets on Graphite substrates. Using X-ray diffraction(XRD) and infrared(IR) show that sediment is deposited in the form of Co(OH)2 on the graphite paper, scanning electron microscopy(SEM) and electrochemical tests show that the deposition time affects the morphology of material, which affect their electrochemical properties, 15 min under the conditions of the preparation of material has good three-dimensional porous structure and specific capacity up to 1246 F/g(b) Selecting the samples of the best deposition time 15 min by low temperature heat treatment, which are translated into Co3O4/EA-Gaphite paper flexible composite membrane materials. Comparing the precursor of Co(OH)2 nano porous, Co3O4/EA-Gaphite paper flexible composite still keep the 3D network structure at the same time and the density of slice layer is bigger. The composite material under the current density of 1 A/g, its specific capacity up to 838 F/g. After 1000 times of charging and discharging cycle after the specific capacity attenuation is only 5%, suggests that the roasting process helps to improve the stability of the material. 3. Nickel fund(hydrogen) oxide preparation and electrochemical properties of nanomaterials research(a) Based on electrochemical oxidation pretreatment of Graphite paper base, on the nickel nitrate solution, prepared by the potentiostatic electrodeposition method the growth of the adhesion on Graphite paper surface of spherical Ni(OH)2. Using XRD and field SEM to characterize the structure and morphology of the product, the XRD results showed that we based in graphite paper succeeded in preparation of Ni(OH)2, using cyclic voltammograms and electrochemical testing methods, such as constant current charge and discharge on the electrochemical properties were studied, the results show that when the deposition time for 30 min of Ni(OH)2 film showed excellent electrochemical capacitor performance, than the single electrode capacitance value up to 1200 F/g.(b) Ni O/EA-Gaphite paper flexible composite film materials are synthesized by the best deposition time 30 min under the condition of the preparation of samples, 3 h, 250℃ heat. Observed by the SEM analysis, formed by a precursor pom-poms morphology, Ni O after sintering, due to the secondary crystallization process, the spherical structure has changed dramatically, namely red assemble into nanometer piece becomes a smooth and beautiful form more open. The composite material under the current density of 1 A/g, its specific capacity can get to 850 F/g. 4. Double metal cobalt, nickel hydroxide extremely electrochemical performance study of preparation of nanometer materialsSome different samples of the proportions of the Ni-Co hydroxide were prepared by the electro-codeposition. when Ni, Co ratio is about 2:1,Ni(OH)2 and Co(OH)2 oxidation reduction reaction match with each other well. And the appropriate cyclic voltammetry curve closest to the ideal curve, which means good reversibility. form mutual crisscross nano flake, stacking and self-assembly growth, form a unique channel of flower ball, the nanometer piece of racial formation of the three-dimensional sphere, overcome the nano piece together, increasing specific surface area material, conducive to rapid transport of electrolyte and electronic, chemical performance is better than the other three mole ratio of the preparation of material. Electrochemical tests show that specific capacitance can get to 1392 F/g, and specific capacity retention have 80%. |
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