Formation of nanoporous oxide at aluminum anodizing

Abstract

The effect of electrochemical anodic oxidation on the formation of porous anodic oxide films (PAOF) on a high-grade aluminum (99.99%) in a sulfuric acid solution is studied. Anodizing modes are chosen such as to obtain PAOF with ordered nanostructure. It is shown that under an atomic force microscope, the anodic film reveals a cellular structure. The parameters of the latter are as follows: diameters of a pore (30–35 nm) and a circle circumscribed around a hexahedral cell (90 nm). A possible mechanism of the formation of regular nanoporous structures of anodic aluminum oxide is proposed.