Nanosized titania encapsulated silica particles using an aqueous TiCl4 solution

In this study, sub-micron sized silica particles were encapsulated with nanosized titania particles using an aqueous TiCl₄ solution. The particle size distribution of the synthesized titania particles in the coating layer was estimated to be 10 nm from X-ray powder diffraction and transmission electron microscopy. The thickness of the coating layer ranged from a few nm to about 30 nm from transmission electron microscopy analysis. Zeta potential analysis demonstrated the presence of a titania particle coating layer and the extent of its coverage on the surface of silica particles. X-ray photoelectron spectroscopy analysis also demonstrated that titania particles were successfully deposited on the surface of core silica particles from the chemical shift of binding energies of O 1s, Ti 2p and Si 2p.