Preparation of luminescent inorganic core/shell-structured nanoparticles

摘要

SiO_2 nanoparticles (NPs) were coated with Eu~(3+)-doped calcium phosphate (CP) and Mn~(2+)-doped ZnO to give Zn_2SiO_4 via a modified Pechini sol-gel process. Annealing at high temperatures resulted in NPs with an amorphous core and a crystalline luminescent shell. It was shown that this procedure can be applied to silica cores with diameters below 300 nm. By transmission electron microscopy, elemental analysis and from X-ray diffraction patterns it was determined that shell composition and structure are influenced by the annealing temperature and pH of the coating solution. Measurements of photoluminescence intensities displayed their dependency on the concentration of dopant in the resulting core/shell NPs.