Self-cleaning glass coated with Fe³⁺-TiO₂ thin film

Abstract

The self-cleaning glass coated with Fe³⁺-TiO₂ photocatalytic thin film was prepared by sol-gel process from the system Ti(OC₄H₉)₄-NH(C₂H₄OH)₂-C₂H₅OH-H₂O containing FeCl₃. The microstructure and properties of the film were studied using differential thermal analysis-thermogravimetry(DTA-TG), X-ray diffration(XRD) and scanning electron microscope(SEM). The transmittance of the self-cleaning glass was measured by using UV-Vis spectrometer. The effects of content of Fe³⁺ and the thickness of Fe³⁺-TiO₂ thin film on the photocatalytic activity were examined. The results show that the photocatalytic thin films are mainly composed of Fe₃O₄ and TiO₂ particles within 10 – 100 nm. The appropriate amount of Fe³⁺ is effective for improving the photocatalytic activities of TiO₂. The best photocatalytic activity is obtained when the molar ratio of Fe³⁺ to TiO₂ is 0.005 and the glass is coated with 9 layers.

Keywords

coating / Fe³⁺ / TiO₂ / self-cleaning glass / photocatalysis / degradation

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