Structural and photoluminescence properties of ZrO2:Eu 3 @ SiO2 nanophosphors as a function of annealing temperature

The synthesis, morphology and luminescence properties of two systems comprising luminescent Eu3+-doped zirconium oxide nanocrystals embedded in an amorphous silica matrix are reported. The two systems, prepared with the same overall wt% composition of silica (75%) and EuxZr(1-x)O(2-x/2) solid solution (25%), have been annealed in the range 135-1000 degrees C and subsequently functionalized with (3-aminopropyl)triethoxysilane. Detailed X-ray diffraction analyses and transmission electron micrographs, combined with infrared spectroscopy and luminescence spectroscopy data, have been used to demonstrate the influence of annealing temperature on the: (i) nanostructure, (ii) luminescence properties and (iii) availability of superficial -OH groups for efficient surface functionalization. The optimum calcination temperature was found to be 700 degrees C for each series in terms of luminescence lifetime efficiency and post-functionalization efficiency with (3-aminopropyl)triethoxysilane. (C) 2010 Elsevier B.V. All rights reserved.