Electrochemical Characteristics of the Anodized Titanium Oxide Films in Sulfuric Acid

This article presents some research into titanium electrode anodizing in H2SO4 solutions in the potential range -1 to 5 V at different scan rates (10, 50, 100 mV s-1) using cyclic voltammetry measurements. Linear potentiodynamic measurements had used before and after the oxide layer formed on the titanium surface. The characterization and the exact determination of the titanium oxides species on the Ti substrate surface had performed by XRD and SEM-EDS analyses. Three characteristic oxide peaks appeared in the electrochemical measurements. These had observed at 0.2 V, 2.3 V, and 3.5 V on cyclic voltammetry curves at all scan rates for all H2SO4 concentrations. Even more, cyclic voltammetry measurements showed that all peaks observed were evident even at higher scan rates. That suggested that robust oxidation of the Ti surface had occurred. Voltammetric tests showed that the passivation of the titanium surface was effective. XRD and SEM-EDS measurements confirmed the existence of TiO2 species in a crystalline form on the titanium surface after anodizing in 3M H2SO4 and annealing the anodized Ti electrode at 400 oC in the airflow. A significant increase in the loading of TiO2 film annealed at 400 oC of the previous anodized Ti anode in H2SO4 was registered.