Aerosol assisted chemical vapour deposition of a ZrO2–TiO2 composite thin film with enhanced photocatalytic activity

Abstract

ZrO₂–TiO₂ composite thin films were deposited by aerosol assisted chemical vapour deposition onto a glass substrate at 450 °C and then annealed at 600 °C. For comparison ZrO₂ thin films and TiO₂ thin films were deposited under the same conditions. X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), UV-Vis and Raman spectroscopy were used to characterize all films. Photocatalytic activities were tested by degradation of intelligent ink containing resazurin redox dye under UVA irradiation. The formal quantum efficiency (FQE) and yield (FQY) for the ZrO₂–TiO₂ composite thin films were determined as 2.03 × 10⁻³ dye molecules per incident photon and 4.91 × 10⁻³ dye molecules per absorbed photon respectively. Surprisingly the ZrO₂–TiO₂ composite was a more efficient photocatalyst than the comparable TiO₂ coating.