The synthesis of ZnO-MgO nanocomposite via modified Pechini method was performed. The crystalline structure and the morphology of nanocrystals were studied by X-ray diffraction analysis and scanning electron microscopy. The study on the kinetics of diazo dye adsorption and its photocatalytic decomposition on the surface of nanocomposite was performed. It was shown that the rate of adsorption process in aqueous solution is described by a kinetic equation of the first order. The application of the nanocomposite allows to significantly increase the efficiency of UV water treatment and its purification from the dye. However, a brief deviation of experimental data on the rate of photocatalytic degradation from the values of the widely used kinetic equation of the first order is observed.

Experimental results of polymer-salt synthesis of Yb:YAG nanopowders and analysis of their structure and luminescent properties are presented. Infrared absorption spectra of synthesized materials are presented. The results of XRD analysis show that Yb:YAG nanocrystals with sizes of 18-35 nm form at a temperature of 900-1100 °С. The study on photoluminescence spectra and decay curves shows that properties of synthesized powders are close to properties of macroscopic materials produced by traditional high-temperature methods.