Synthesis and UV-shielding Property of Plate-like Potassium Lithium Titanate Coated with Calcia-doped Ceria Nanoparticles

Abstract

In order to attain further performance improvements concerning UV-shielding, the synthesis parameters of plate-like lepidocrocite related potassium lithium titanate were optimized and calcia-doped ceria (Ce0.8Ca0.2O1.8) nanoparticles were coated on plate-like potassium lithium titanate (K0.8Li0.27Ti1.73O4), 10-20 μm in diameter via solution processes, where the plate-like titanate was prepared by reacting K2CO3, Li2CO3 and TiO2 using KCl flux at 950°C. After putting plate-like potassium lithium titanate particles in deionized water at 40°C, appropriate quantities of 3 M NaOH aqueous solution and 0.8 M CeCl3-0.2 M CaCl2 mixed aqueous solution were simultaneously dropped, where the solution was stirred and pH was kept at 12 throughout the reaction. Then, the desired amount of 2 M H2O2 solution was added and pH was also kept at 12. The slurry was filtrated and washed with water and methanol. The precipitate was fired at 700°C for 1 h to obtain plate-like K0.8Li0.27Ti1.73O4 coated with white Ce0.8Ca0.2O1.8 nanoparticles. Such panoscopic assembling successfully improved the comfort of the product when wearing it on the skin without compromising the UV-shielding ability, meanwhile greatly reducing the oxidation catalytic activity.