Influence of the HClO4Concentration over the Morphology and Growth of TiO2Anodic Porous Films Formed in 5 mM HF/xM HClO4(0.05 M ≤ x≤ 1M)

In the present work the effect of the HClO4 concentration over the morphology and growth of anodic Ti oxide films in fluoride containing electrolytes is studied. The voltammetric behavior of the Ti is not considerably affected by HClO4 concentration, showing a current plateau in a high potential range in which the anodic films were potentiostatically grown (6.5 V). Even when the SEM images evidenced a decrease in pore diameter with the increase of perchloric acid concentration, the recorded chronoamperograms did not show any considerable changes in the growing of the films. However, in the EIS spectra, it is observed a modification of the high frequency components, provoked by the detriment in the oxide film resistance and capacitance, allowing the correlation between the barrier layer thickness and resistance with the pore diameter of the external porous layer formed.