Photocatalytic characteristics of TiO ₂ films deposited by magnetron sputtering on polycarbonate at room temperature

Anatase TiO ₂ thin films were successfully grown at room temperature on polycarbonate substrates, using RF magnetron sputtering under various conditions. The deposition parameters used to examine the photocatalytic activity of TiO ₂ films included RF power, sputtering pressure, argon/oxygen ratio (O ₂ /(Ar + O ₂ )) and deposition time. An orthogonal array and analysis of variance (ANOVA) were used to determine the performance of the deposition process. The effects of the deposition parameters on the structure, morphology and photocatalytic performance of TiO ₂ films were analyzed using scanning electron microscopy (SEM), X-ray diffraction, a contact angle meter and UV/vis/NIR spectroscopy. The RF power was found to be the factor that most affected the water droplet contact angle and the sputtering pressure was found to be the second ranking factor. The results indicate that the photocatalytic performance is improved by increasing RF power, but an increase in sputtering pressure has an adverse effect. Higher photocatalytic activity is achieved for TiO ₂ films using an RF power of 210 W, sputtering pressure of 0.93 Pa, argon/oxygen ratio of 30% and a deposition time of 2 h.