Influence of annealing temperature on structure and photocatalytic activity of TiO2 thin films prepared by DC reactive magnetron sputtering method

Abstract

Transparent TiO2 thin films were successfully prepared on high purity silica substrates by DC reactive magnetron sputtering method and annealed at different temperatures. The effects of the annealing temperature (300–600 °C) on crystalline structure, morphology, and photocatalytic activity of the TiO2 thin films were discussed. The photocatalytic activity of the films was evaluated by photodegradation of methylene blue solution. With increasing annealing temperature, the photocatalytic activity of the TiO2 thin films gradually increased because of the improvement of crystallization of anatase TiO2 thin films. At 500 °C, the TiO2 thin film shows the highest photocatalytic activity due to the improvement of crystallization of anatase TiO2 thin films. When the annealing temperature increases to 600 °C, the photocatalytic activity of thin film decreases owing to the formation of rutile phase and the decrease of surface area.