Photocatalytic properties of Cr-TiO2 nanocomposite photoelectrodes produced by electrochemical anodisation of titanium

摘要

Different Cr-TiO2 nanocomposite photoelectrodes were fabricated by in situ anodisation of titanium in a single step process using potassium chromate as the chromium source. The morphology and structure were characterised by field emission scanning electron microscopy, X-ray diffraction and energy dispersive X-ray spectroscopy. Optical properties were investigated by UV-Vis diffuse reflectance spectra. The visible light photocatalytic activity of the Cr-TiO2 nanocomposite photoelectrodes was evaluated by measuring the degradation of rhodamine B dye under visible light irradiation. The results showed that Cr-TiO2 nanocomposite electrodes have excellent photocatalytic performance. Cr-TiO2 nanocomposite produced using 5 mM K2CrO4 exhibited better photocatalytic activity than did the pure TiO2 and Cr-TiO2 nanocomposite fabricated using other chromium concentrations. The anodisation process developed in this study is facile, reproducible and inexpensive and can be easily scaled up, thereby pioneering the fabrication of high performance photocatalysts with promising environmental applications.