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Photoactive Cu-doped ZnO-ZnAl 2 O 4 ceramic nanocomposites and coatings were prepared by polymersalt method. The luminescent and IR spectroscopy, SEM and XRD methods were used for the study the structure, morphology and materials properties. The nanocomposites consist of small hexagonal ZnO and cubic ZnAl 2 O 4 nanocrystals having size about 10 nm. The study of luminescence properties shows that prepared nanocomposites can be used as light down-converters that transfer UV-C radiation into UV-A and visible spectral range. These nanocomposites can be very attractive in photovoltaic applications as spectral down-converters. Also obtained nanocomposites demonstrate the ability to generate chemically active singlet oxygen under UV-A radiation and blue light. The experiments show that Cu-doped ZnO-ZnAl 2 O 4 materials demonstrate antibacterial activity against gram-positive bacteria.

In this work, the adsorption and photocatalytic properties of ZnO-ZnAl2O4 nanosized composites synthesized by the polymer-salt method have been studied. To evaluate the efficiency of adsorption, experiments were carried out on the decolorization of aqueous solutions of the Chicago Sky Blue diazo dye. The adsorption process is divided into two stages, at the first stage the dye is rapidly adsorbed on the outer surface of the composite particles, at the second stage the dye diffuses into the pores of the material. It was noted that the rate of photocatalytic decomposition of the dye is higher than the rate of the adsorption process, which indicates the occurrence of photocatalytic decomposition of dye molecules both on the surface of the composites and in the liquid phase. With an increase in the light intensity, the photocatalytic process is significantly accelerated, linearly at low intensities, and at high intensities the dependence becomes a power law.

Photoactive Cu-containing ZnO-ZnAl2O3 nanocomposites were synthesized by the polymer-salt method. To study the structure and properties of materials, the methods of luminescent spectroscopy and X-ray phase analysis were used. It has been shown that the resulting nanocomposites are capable of photogeneration of singlet oxygen under the action of UV and blue light. The synthesized materials consist of nanosized hexagonal ZnO crystals and cubic ZnAl2O4 crystals doped with Cu. The study of luminescent properties showed that nanocomposites can be used as down-converters of light that convert radiation from the UV-C range to UV-A and the visible spectral range. Keywords: singlet oxygen, nanoparticle, luminescence, ZnO, ZnAl2O4.