Complex Morphology Of The Electrode Compatibilization Mechanism

Electrode materials with complex surface shape always have important application value, and it is an important research topic to study the functional properties of these electrodes and to find out physical and chemical mechanisms of performance-improving. This dissertation carried out a research on aluminum electrode material with complex surface shape, which is uesed in the aluminium electrolytic capacitors. At first, we described various methods of increasing the special capacitance of aluminum foils, including means of electrochemical corrosion and high dielectric composite oxide films preparation, then physical and chemical mechanisms corresponding were analyzed and discussed.It is a key factor of producing capacitors with high quality to increase the special capacitance of aluminum electrode materials. Currently aluminum foil manufacturing technology enables the aluminum foil to enhance the performance greatly. Reserches on various technologies of high specific-capacitance foil were expected to enhance the domestic capacitor industry furtherly. Therefore, this dissertation established a compatibilization model based on aluminum foils. Effective surface area S and the formation constant of oxide film K were used as key parameters to measure capacitance-improving. In order to obtain accurate data on S and K efficiently, we found a special experimental method--interface electrochemical measurement method, including surface weight method and the interface charge method. The experiment successfully and effectively obtained the data of S and K.After validating the compatibilization model and testing the accuracy of the experimental method, this dissertation analyzed the compatibilization mechanism of aluminum corrosion foils with different process, such as'alkaline'and'acidic'process, and then successfully explained the phenomenon of elevated specific capacitance broutht by the alkaline process. This dissertation also studied a series of high-dielectric-property composite film technologies, providing the specific volume curves of various methods. Research was made on different methods based on the compatibilization model, and physical mechanism of composite oxide film technology was discussed preliminary.The capacitance properties of anodic oxide film on different anodic voltage were examined by elechrochemical impedance spectroscopy measurement. Equivalent circuit model changed when aluminum foil was anodized on voltage higher than 35 volt. Refering to the slope of the S-V curve, obvious submerging phenomenon of small corrosion holes was confirmed. Through the study on the corrosion technology, we advised to produce corrosion foil with more large-size holes through adjusting the process parameters during the corrosion stage.