Synthesis and photolysis of NaYF4@SiO2@TiO2 core–shell nanocomposites

Abstract Monodisperse β-NaYF 4 nanocrystals were synthesized with oleic acid as capping ligands by solvothermal method, and then, SiO 2 and TiO 2 were coated successively. Intense ultraviolet light is emitted from NaYF 4 :Yb/Tm under the 980 nm laser and the intensity of ultraviolet light reduce dramatically after these nanocrystals were coated with SiO 2 and TiO 2 shells, which means NaYF 4 @SiO 2 @TiO 2 core–shell nanocomposites can be used to realize the infared photocatalysis. Photocatalytic activity of these nanocomposites is demonstrated using methyl orange (MO) as a chemical probe under the 980 nm laser excitation.