Galvanoluminescence properties of porous oxide films formed by anodization of aluminum in malonic acid

The influence of anodic conditions on the intensity of galvanoluminescence (GL) and shape of the GL spectra of porous oxide films formed by aluminum anodization in malonic acid aqueous solution was investigated. We have showed that there are wide GL bands in the visible region of the spectrum and observed two dominant spectral peaks. The position as well as the relative ratio of the spectral peaks depends on the voltage of anodization and the temperature of electrolyte. Also, our results have showed that GL is more intense at lower temperature of electrolyte and higher current density. Comparison with GL spectra of porous oxide films in organic carboxylic electrolytes indicates the same type of luminescence centers responsible for GL in this type of electrolytes. Energy dispersive spectroscopy (EDS) as well as Infrared Fourier Transform (ATR-FTIR) spectroscopy confirmed the correlation between GL spectra and incorporation of carboxylic species during anodization in carboxylic acids.