Photocatalytic reduction of Cr(VI) in aqueous solution using TiO2 nanoparticles prepared with various alcohols as solvent

TiO2 nanoparticles were prepared with various linear alkyl chains of alcohols under a sol-gel process. The structure characterization and the photocatalytic reduction of hexavalent chromium of the TiO2 nanoparticles were investigated. The phase transformation temperature, crystal aggregation and surface area of prepared TiO2 samples were found to be strongly influenced by alcohol used. The phase transformation from anatase to rutile was retarded and the surface area was reduced for TiO2 prepared with alcohols of longer alkyl chain. TiO2 nanoparticles prepared with methanol or ethanol exhibited higher photocatalytic reduction activity of hexavalent chromium possibly due to greater and more positively charged surface area.