The Application of Anodizing for Hybrid Capacitor
Anodizing is widely studied because of its good advantages such as low cost and tractability in over a wide industrial area as one of the surface treatment processing technologies. Thus the anodized metal electrode is used as anode electrode of an electrical circuit. Consequently this process is named anodizing. Recently this process has the limelight to fabricate nano-scale structure with aluminum and titanium metals, etc. For these reasons anodizing have been used for fabrication of nano-scale linear materials and this linear type materials are applied to functionality inorganic membrane, photonic crystals, bio sensor, and electrode in energy storage devices
The template was prepared by anodizing of 99.99% pure aluminum template of 0.2 mm thickness at 40V in 0.3 mol dm-3 sulfuric acid electrolyte at 20 ̊C. It was used as working electrode, and an aluminum sheet was also used as a counter electrode. After anodizing, pore-widening treatments were conducted by immersing the anodic alumina template obtained in 5wt% phosphoric acid at room temperature for 2 hours.
Then, the mixture of anodic porous templates and carbon resource was heated in argon at 300 ̊C and kept at this temperature for 30min. After that, the temperature increased up to 600 °C and kept for 1 hour. In this heat treatment, the carbon resource was decomposed to liquefy into porous structure of template. And templates were dissolved in 10% NaOH solution and the CNFs formed were filtered. The morphologies and structures were examined using SEM, Tem, Impedance analysis, Cyclic-voltammetry and Charge-discharge analysis.
Result & Discussion
Figure shows SEM images of the AAO templates after pore-expansion treatment with 2nd anodized AAO templates. The effects of the two-step anodizing process can be seen clearly, and we can confirm that the AAO template shows a well-ordered pore distribution and increase of pore diameter according to pore-expansion time after the second anodizing step.
 M. Kiriu, M. Hayashi, H. Konno, H. Habazaki, Materials Chemistry and Physics, 105, (2007) 367-372.
 M. Kiriu, H. Konno, H. Habazaki, Electrochemistry Communications, 8, (2006) 1275-1279.