Impedance of an Aluminum Electrode with a Nanoporous Oxide

The methods of electrochemical impedance spectroscopy and electron microscopy with X-ray electron probe analysis are used to study two types of oxide films on aluminum: a smooth compact one and a porous one (nanooxide) formed by two-stage oxidation. An equivalent circuit is chosen that agrees well with the obtained impedance spectra and allows estimating the thickness and conductivity of barrier oxide layers and also the area occupied by nanopores for various film types.