Preparation and optical properties of core-shell CaF2:Yb, Er@SiO2 nanoparticles

High quality CaF₂: Yb, Er @ mesoporous SiO₂ core-shell nanoparticles were prepared by coating silica shell onto solvothermal synthesized CaF₂: Yb, Er nanoparticles through reverse microemulsion and liquid crystal template processes. The phase identification, morphology and upconversion luminescence properties of CaF₂: Yb, Er @SiO₂ core-shell nanoparticles were investigated in detail. The results show that CaF₂: Yb, Er nanocrystals are of cubic structure and SiO₂ shell is mesoporous. The core-shell structure has little effect on the upconversion properties of CaF₂: Yb, Er nanoparticles. And the nanocomposites with upconversion luminescent CaF₂: Yb, Er nanocrystals core and a mesoporous silica shell are potential photocontrollable drug vehicles.