Adsorption and photocatalytic decomposition of organic molecules on carbon-coated TiO2

Carbon-coated anatase TiO2 samples were prepared from the mixture of poly vinyl alcohol (PVA) and commercial TiO2 (P-25) with different mass ratios and heating temperatures. The samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), energy dispersive spectrometer (EDX), transmission electron microscope (TEM), and nitrogen adsorption analyses. The adsorption properties and photocatalytic activity of commercial and carbon-coated TiO2 catalysts were compared for the oxidation of methylene blue (MB) and bisphenol-A (BPA). It was interesting to find that the transition from anatase to rutile was suppressed by carbon coating of TiO2 at high temperature up to 800 degrees C. The carbon-coated TiO2 samples have a higher surface area and a greater adsorption amount than commercial P-25 because of the thin layer of carbon that covered TiO2. It was also observed that the photodecomposition efficiency was dependent on the crystallinity of the carbon-coated sample.