A method to produce robust magnetic particles coated with TiO₂ nano particulates

This work presents an approach to produce reusable magnetic particles coated with commercially available titania (P25) for use in the treatment of drinking water supplies. Robustness was achieved by depositing a topcoat of a sol-gel silica or titania that acts as a glue for anchoring the P25 particles to the underlying magnetic core. While the silica topcoat provided the necessary robustness, also lowered activity compared to those without the silica topcoat. In contrast, the TiO2 topcoat provided the necessary robustness and had a higher catalytic activity those without the titania topcoat. This higher activity is attributed to an increase in the number of the hole-electron pairs generated and an increase in the surface area of the photocatalyst. This approach to achieving robustness could be applied to other photocatalytic particles and addresses a need to develop approaches for solving issues related to the practical use of such photocatalysts in field applications.