ZnO:CeO2-based nanopowders with low catalytic activity as UV absorbers

Ultrafine systems of zinc oxide and cerium oxide for use as ultraviolet filter were synthesized by a non-alkoxide sol–gel process at different temperatures, to obtain solid materials (40 and 70 °C), that were characterized by X-ray diffraction, scanning electron microscopy, UV–vis reflectance. Their catalytic and photocatalytic activities were also evaluated. ZnO:CeO2 systems present higher UV absorption and transparency in the visible region. The photocatalytic activity of ZnO:CeO2 systems for the oxidation of organic materials is much smaller than that of titania, ceria and zinc oxide, suggesting that ZnO:CeO2 systems are promising candidates for use as optical materials in UV-filters.