A novel magnetic nanocomposite involving anatase titania coating on silica-modified cobalt ferrite via lower temperature hydrolysis of a water-soluble titania precursor

A high surface area magnetic nanocomposite titania/silica/cobalt ferrite photocatalyst was synthesized via controlled hydrolysis and condensation of water-soluble titanium bis-ammonium lactato dihydroxide at relatively lower temperature (<97 °C) and characterized by XRD, FTIR, HRTEM, BET, XPS and magnetism analysis. The results reveal that as-prepared photocatalyst possesses a core/shell structure involving ferrite particles sequentially coated with coherent silica layer and anatase nanocrystallites via a heterogeneous nucleation and growth mechanism. The photodegradation of the photocatalyst for methyl orange is comparative to Degussa P25 and higher than the heated samples, being tentatively attributed to the proper microstructure and isolation/immobilization functions by silica intermediate phase as well as the surface-bond hydroxyl groups.