Fabrication and ultraviolet-shielding properties of silica-coated titania-doped ceria nanoparticles

A series of well-dispersed titania-doped ceria nanoparticles Ce1-xTixO2 were rapidly prepared by a novel salt-assisted solution combustion process using correspondent metal nitrates as oxidizers and ethyl glycol as fuel, and then coated with amorphous silica by seeded polymerization using tetraethyl orthoslicate (TEOS). The as-prepared samples were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and ultraviolet-visible light (UV-Vis) diffuse reflectance spectroscopy. The results indicated that compared with the as-prepared pure ceria nanoparticles, the red-shift phenomenon occurred for Ti-doped ceria nanoparticles with Ti incorporation. Meanwhile, the absorption intensity in the UV light region slightly decreased and transmission rate in visible light region was somewhat enhanced. In comparison with the silica-coated CeO2 nanopowders, the silica-coated Ce0.95Ti0.05O2 nanopowders displayed the same absorption intensity in the UV light region, broader UV absorption band and higher transmission rate in visible light region.