Low-temperature preparation of anatase titania-coated magnetite

Abstract

A composite photocatalyst with an anatase titania shell and a magnetite core was prepared in a novel way at low temperature (75 °C at most) by coating photoactive titanium dioxide onto a magnetic Fe 3O 4 core. The photocatalytic activity of the prepared photocatalyst was evaluated by the degradation of model contaminated water of phenol and compared to single-phase titania (either Degussa P25 or prepared titania without magnetic Fe 3O 4). The results showed that the photoactivity was slightly depressed. Then, a remarkable improvement in photoactivity was achieved by modifying the photocatalyst with a SiO 2 layer between the Fe 3O 4 core and TiO 2 shell. The repetitive using of the modified photocatalyst was also investigated, and experimental results illustrated that the photocatalytic-degraded ratio of phenol was still higher than 80% after six cycles.