ZnO/TiO2 thin films for photocatalytic application

Abstract

ZnO/TiO2 thin films have some advantages such as can enhance the surface state and surface atomic mobility which are useful for improving the photocatalytic activity. The motivation to used double layer of ZnO and TiO2 is to enhance photocatalytic activity using the different deposition temperature between the layer. The structural properties and photocatalytic activity of ZnO/TiO2 thin films with calcination temperature as parameter were studied. It is found that ZnO (600 °C)/TiO2 (500 °C) thin film consists of ZnO with zincite structure and TiO2 with anatase structure while the other ZnO/TiO2 thin films only exhibit TiO2 with anatase structure. The X-Ray Diffraction (XRD) patterns become more intense and sharper when the calcination temperature increases. Field Emission Scanning Electron Microscope (FESEM) was used to determine the surface morphology of ZnO/TiO2 thin films. The results showed that surface morphology of ZnO/TiO2 thin film becomes rougher but homogeneous. Size of particles also becomes smaller when the calcination temperature increases. The photocatalytic activity of ZnO/TiO2 thin films was analyzed using photodegradation of methylene blue (MB) solution. A higher calcination temperature of ZnO buffer layer leads to enhance the degradation efficiency of MB dye using ZnO/TiO2 thin films as photocatalysts. It is proposed that the ZnO/TiO2 thin film with higher calcination temperature can be an efficient photocatalyst under UV irradiation.ZnO/TiO2 thin films have some advantages such as can enhance the surface state and surface atomic mobility which are useful for improving the photocatalytic activity. The motivation to used double layer of ZnO and TiO2 is to enhance photocatalytic activity using the different deposition temperature between the layer. The structural properties and photocatalytic activity of ZnO/TiO2 thin films with calcination temperature as parameter were studied. It is found that ZnO (600 °C)/TiO2 (500 °C) thin film consists of ZnO with zincite structure and TiO2 with anatase structure while the other ZnO/TiO2 thin films only exhibit TiO2 with anatase structure. The X-Ray Diffraction (XRD) patterns become more intense and sharper when the calcination temperature increases. Field Emission Scanning Electron Microscope (FESEM) was used to determine the surface morphology of ZnO/TiO2 thin films. The results showed that surface morphology of ZnO/TiO2 thin film becomes rougher but homogeneous. Size of particles also becomes sm...