Characterization of nanopores arrangement of anodic alumina layers synthesized on low-(AA1050) and high-purity aluminum by two-step anodizing in sulfuric acid with addition of ethylene glycol at low temperature

Abstract

In this work the anodic aluminum oxide (AAO) was produced by two-step self-organized anodization of two classes purity aluminum in 0.3 M sulfuric acid aqueous solution with addition of ethylene glycol as the solution modifier. The arrangement analysis method based on fast Fourier transforms was applied to characterize the porous arrays ordering. The quality, arrangement, circularity and regularity of nanoporous AAO formed on the low-purity (AA1050) and high-purity aluminum were investigated in details. It was found that the regularity of the nanopores ordering obtained on low-purity aluminum at applied experimental conditions was extraordinarily high while compared to the data published previously. The relation between the structural features of nanopores as well as aluminum concaves ordering obtained in two-step anodization process depending on the step of reaction, was analyzed. It was proven that purity of anodizing aluminum influence the interpore distance, wherein the purer aluminum the smaller interpore distance. The observed phenomenon was discussed in details in accordance with intrinsic mechanism. Furthermore, there are no simple relations between regularity ratio of obtained nanostructures and the step of anodizing.