Spherical nanoparticles of ZrO with 2 and 10 mol% EuO up to 20 nm size were prepared by the method of hydrothermal synthesis for luminescent functionalization of the polymer-inorganic nanocomposites based on poly(methyl methacrylate). Surface modification of oxide nanoparticles was carried out by 3-(trimethoxysilyl)propyl methacrylate, dimethoxymethylvinyl silane and 2-hydroxyethyl methacrylate to provide uniform distribution and to prevent agglomeration of nanosized filler in the polymer matrix. Polymer-inorganic composites were synthesized by in situ free radical polymerization in bulk. Structuring of ZrO -EuO nanoparticles in the poly(methyl methacrylate) was studied by very-small-angle neutron scattering. According to the results, the dependence of photoluminescent properties of ZrO -EuO nanoparticles on the content of lanthanide, the symmetry of the crystal field, surface treatment and the polymer matrix were established. A correlation was shown between Stark splitting in luminescence spectra of ZrO -EuO nanoparticles and their phase composition. Using MMT-assay it was shown that composites based on poly(methyl methacrylate) and ZrO -EuO nanoparticles do not have cytotoxic properties, which makes it possible to use them as prosthesis materials with contrasted and luminescent imaging properties.

Luminescent zirconia nanoparticles with europium ion content 1 and 10 mol.% were synthesized under hydrothermal conditions. Annealing of ZrO 2 : 1 mol. Eu 3+ nanoparticles made it possible to obtain a sample with a high monoclinic phase content up to 92 %. An increase in the concentration of Eu 3+ ions introduced into the zirconia crystal lattice has made it possible to almost completely convert its monoclinic and tetragonal phases into cubic modification. The phase composition of the synthesized samples was determined by powder X-ray diffraction, electron microdiffraction, and Raman spectroscopy. Analysis of the crystallographic data and the luminescent spectra helped to reveal correlations between the ZrO 2 :Eu 3+ nanophosphor structure and the energy redistribution of Eu 3+ optical transitions at 614 -626 nm and 606 -633 nm wavelengths. In addition, a relationship was established between the phase composition of nanoparticles based on zirconia and the luminescence lifetime of Eu 3+ ions.

ZrO 2 nanoparticles doped with 2 mol.% of EuO 1.5 were obtained from solutions of inorganic salts, zirconium alkoxide and chelating compounds under hydro and solvothermal conditions. The phase compositions of the synthesized nanophosphors were determined using the methods of X-ray diffraction, photoluminescence and Raman spectroscopy. The changes in a particle size, the value of the specific surface area and its charge depending on the conditions of preparation (the type of solvent, isothermal exposure time) and the precursor nature used in the synthesis were considered. It was found that Zr 0.98 Eu 0.02 O 1.99 nanoparticles with a high content of the monoclinic phase, synthesized from zirconium and europium acetylacetonates, have the highest luminescence efficiency. At the same time, the maximum photoluminescence lifetime and the least cytotoxicity were characteristic of crystal phosphors with a more symmetrical crystal lattice of the host matrix, as well as a high surface area/volume ratio.

No abstract