Formation and Dissolution Behavior of Anodic Oxide Films on Titanium in Oxalic Acid Solutions

Abstract The effect of temperature, oxalic acid concentration, and pH of solution on the growth and dissolution of anodic oxide films on titanium has been investigated using electrochemical impedance spectroscopy (EIS), galvanostatic measurements, and open-circuit potential measurements. An increase in temperature and electrolyte concentration leads to a decrease in the oxide film growth and an increase in the dissolution process of the oxide films. The rate of oxide film formation decreases with lowering the pH of solution from pH = 7 to pH = 2 while the rate of film dissolution increases. The activation energies for the oxide film growth and dissolution processes were calculated and found to be 19.59 kJ/mol and 34.29 kJ/mol, respectively. An equivalent circuit describing the oxide film/electrolyte interface is suggested. The effect of current density on the formation rate of the oxide film was measured. The reciprocal capacitance data was reported as a function of polarizing current density.