Preparation and photocatalytic activity of rutile TiO2 and goethite composite photocatalysts

Rutile TiO2 and goethite (alpha-FeOOH) composite photocatalysts were fabricated by hydrolysis and precipitation using titanium tetrachloride as a precursor and alpha-FeOOH as a support. The samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. The results show that at lower temperature, rutile TiO2 particles coat on the surface of alpha-FeOOH particles to form rutile TiO2-alpha-FeOOH composite photocatalyst. At higher temperature, iron ions are doped into the rutile TiO2 lattice to form iron-doped rutile TiO2 tubes; at medium temperature, the sample is a mixture with both composite and iron-doped structures. The photocatalytic activity of the samples is estimated by their ability to degrade methyl orange under irradiation with ultraviolet-visible light (200-800 nm) at ambient temperature. The photocatalytic activities of the samples are improved compared with that of pure rutile TiO2 and alpha-FeOOH. The sample containing a mixture of composite and iron-doped structures shows the highest photocatalytic activity of that investigated. As a result, the photocatalytic activity of Ti2O could be improved effectively by combining with alpha-FeOOH or doping iron. (c) 2013, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.