Micro and Nanostructure Surface and Interface Characterization of Anodized Zr in Two Different Electrolytes

The present work reports on the morphologies and properties of anodized Zr in two different electrolytes. The Zr phosphates (?-ZP) obtained in the inorganic electrolyte containing H3PO4+NaF and zirconia (ZrO2) nanostructures formed in the organic glycerol-based electrolytewere investigated by SEM, FT-IR and AFM. The surface analysis was completed by contact angles measurements. It was found that the type of electrolyte along with the applied voltage influence the structure of the sample and being more precise, the anodic oxidation in H3PO4 electrolyte promotes the evolution of flaky structures and eventually of pores by increasing the applied voltage, while the anodizing performed in glycerol-based electrolyte results in the formation of nanoporous structures that evolve into nanotubes as the applied voltage grows. Based on experimental data a film forming mechanism for ?-ZP and ZrO2 was proposed and correlated to analyzed surface properties.