Investigation of the Ordering of Porous Anodic Alumina Formed by Anodization of Aluminum in Selenic Acid

The formation of porous alumina by galvanostatic anodization in selenic acid has been investigated. The influence of the electrolyte concentration on the morphological features and the self-ordering behavior of the porous oxide film has been studied. The best pore arrangement is obtained upon anodization in 0.5 M H2SeO4. Using chronopotentiometry, gravimetric analysis and FESEM it is shown that the highest degree of pore ordering is caused by an optimal combination of the two mechanisms that lead to pore initiation: mechanical instability and field-assisted dissolution. In addition, by means of Raman spectroscopy it is found that the optical properties of porous alumina anodized in selenic acid do not exhibit parasite effects due to electrolyte incorporation during anodization. Hence, these templates are of great interest to fabricate and investigate functional nanostructures for optoelectronics. (C) 2015 The Electrochemical Society. All rights reserved.