Effect of anodizing time and annealing temperature on photoelectrochemical properties of anodized TiO₂ nanotube for corrosion prevention application

A study on the influence of anodizing time, annealing temperature and photoelectrochemical properties of TiO₂ nanotube (TiO₂ NT) has been investigated. The crystallinity was investigated using X-Ray Diffraction and the anticorrosion performance of stainless steel 304 (SS 304) coupled with TiO₂ NT was evaluated using electrochemical techniques under ultraviolet exposure. The optimum anodizing condition occurs at a voltage of 20 V for 3 h. After anodizing, the TiO₂ NT amorf was calcined at 500 °C to obtain anatase crystalline phase. For the photoelectrochemical property, the effects of pH and NaCl concentration on corrosion prevention have been examined. The result showed that the corrosion rate of stainless steel 304 coupled with TiO₂ NT can be reduced up to 1.7 times compared to the uncoupled stainless steel 304 (3.05×10^-6 to 1.78×10^-6 mpy) under ultraviolet exposure by shifted the photopotential to the more negative value (-0.302 V to -0.354 V) at a pH of 8 and 3% NaCl concentration (-0.264 V to -0.291 V). In conclusion, the TiO₂ NT films, which was prepared by anodization and followed by annealing can prevent the corrosion of stainless steel 304.