Summary: | 碩士 === 國立成功大學 === 材料科學及工程學系碩博士班 === 94 === The electrode materials of supercapacitor are important research targets, recently. Manganese oxide is one of the promising electrode materials. The specific capacitance of manganese oxide are affected by many factors, however, until now there is no any report about the contribution of each factor to the specific capacitance of manganese oxides. This study tries to prepare the manganese oxide film on the titanium metal plate by galvanostatic anodic deposition to get the electrode membrane of capacitors. The Taguchi method was used to analyze the contribution of deposition temperature、current density、Mn(CH3COO)2.4H2O concentration and pH to the specific capacitance of manganese oxides. The cyclic voltammetry was used to test the pseudocapacitor behavior and specific capacitance in 0.1 M Na2SO4 solution. The results showed that the sequence of factors with respect to the contribution to specific capacitance of manganese oxides were the deposition temperature、current density、interaction between deposition temperature and current density, and concentration of Mn(CH3COO)2 solution, when the deposition temperature ranges from 5 ℃ to 25 ℃, pH ranges from 5.3 to 7.3, Mn(CH3COO)2.4H2O concentration ranges from 0.05 M to 0.5 M and current density ranges from 0.25 mA/cm2 to 2.25 mA/cm2. The interaction between deposition temperature and current density was important, and its contribution to specific capacitance of manganese oxides was 15.04 %.
Effect of the deposition temperature(5~80℃) on the specific capacitance of manganese oxides was also discussed because the deposition temperature was the main factor. The experimental results showed that the manganese oxides deposited at 15 ℃ exhibited the highest specific capacitance of 225.3 F/g and the specific capacitance remained 85 % after 300 CV cycles.
|