Fabrication and characterization of Ag-implantation modificated TiO2 films followed with thermal annealing

TiO2 thin films fabricated by direct-current (DC) reactive magnetron sputtering were implanted with Ag ions at 30 kV to fluences of 1 × 1016, 3 × 1016 and 5 × 1016 ions/cm2, and subsequently annealed at 500 °C for 2 h under Ar ambient. Cross-sectional transmission electron microscopy and X-ray photoelectron spectroscopy studies showed that the implanted Ag ions were incorporated in TiO2 to form Ag2O after thermal annealing. The Ag-implanted TiO2 film with fluence of 3 × 1016 ions/cm2 after an annealing showed improved photocatalytic efficiency comparing to TiO2 film. When the implantation fluence increased to the 5 × 1016 ions/cm2, the sample showed poorer phtotcatalytic efficiency. These results indicate that there exists an optimum Ag ions implantation fluence. The photocatalytic behavior can be explained by the effect of Ag+ on the physicochemical properties in terms of electronic structures and film texture.