In-situ fabrication of TiO<inf>2</inf>-C core-shell particles for efficient solar photocatalysis

© 2018 Elsevier Ltd A facile method is proposed for the in-situ synthesis of titania-carbon (TiO2-C) core-shell composite structures with ameliorated photocatalytic properties. The particles were prepared by controlled hydrolysis of titanium alkoxides followed by calcination in a non-oxygenating atmosphere. To study the effect of fabrication technique on the size and morphology of the prepared catalyst, three different combinations of precursors and solvents were investigated. Phase purity, physical and chemical characterization of the as-synthesized catalysts were confirmed using X-ray diffraction, scanning electron microscopy, diffuse reflectance spectroscopy and Raman spectroscopy techniques. Photocatalytic activity of the catalyst was evaluated by monitoring mineralization of methylene blue dye solution under solar illumination. It was observed that compared to standard titania, samples containing carbon were up to eight times more efficient at achieving solar assisted mineralization of dye. Subsequent analysis revealed that choice of titanium alkoxide and solvent (alcohol) can significantly affect the crystallite size, color and surface area of the calcined samples. The enhanced photocatalytic activity of the TiO2-C catalysts can be attributed to improved visible light absorption and a larger surface area