Multilayered TiO_2/TiO_(2-x)/TiO_2 films deposited by reactive sputtering for photocatalytic applications

摘要

Multilayered TiO_2/TiO_(2-x)/TiO_2 films, deposited by twenty periodical interruptions of O_2 flow during reactive sputtering deposition were submitted to photocatalytic tests and characterized. The O_2 flow interruptions lasted 10 s, 38 s, 45 s, and 70 s, while the regular flow periods lasted 540 s.The photocatalytic tests were performed using UV irradiation from a mercury lamp and a solution of methylene blue dye. The best photocatalytic response was observed in samples corresponding to 10 s interruptions. The results show that the amount of degraded dye was increased by an average of 1.67 times in the interrupted flow sample as compared to the homogeneous TiO_2 film deposited under similar conditions. The results show that this relatively simple deposition procedure can produce significant improvements to the photocatalytic activity of the TiO_2-based catalysts.