LUMINESCENT PROPERTIES OF ALUMINUM OXIDE SYSTEMS CONTAINING RARE EARTH ELEMENTS OBTAINED BY ELECTROCHEMICAL METHOD

The study is devoted to obtaining and investigating the luminescent properties of precursors of complex oxide systems containing rare earth elements obtained by electrochemical methods. The formation of precursors of oxide systems is based on the processes of anodic dissolution of aluminium in a chloride-containing electrolyte in the presence of Al(III), Zr(IV), Dy (III), Nd (III) ions, due to co-precipitation in the presence of electro-generated OH- ions. The influence of the ionic composition of the electrolyte and the pH of the co-precipitation on the physicochemical properties of the materials, including at the molecular level, is shown. The synthesised dispersed aluminozirconium oxide systems with REEs demonstrate clearly expressed luminescent properties. All dispersed oxide systems, when excited by UV light at a wavelength of 250 nm, demonstrated luminescence in the UV and visible regions of the spectrum with maxima at wavelengths of 360, 380 and 700 nm. When comparing the spectra obtained for systems doped with rare earth oxides with the bands of the base system Al2O3-ZrO2, it was found that their character remained practically unchanged, but in the case of systems containing neodymium and dysprosium oxides, an increase in luminescence intensity (hypochromic effect) by 3.5-4.3 times was observed. In the system doped with dysprosium oxide, an increase in the peak shoulder in the 450-500 nm region was observed. Presumably, this is due to a change in the structure of the doped oxide systems compared to the base Al2O3-ZrO2 system. In the IR region of the spectrum, the neodymium-modified alumina system exhibits distinct luminescence peaks at wavelengths of 1070 nm and 1340 nm, corresponding to the 4F3/2→4IJ (J=11/2, 13/2) transitions of the Nd3+ ion. In the case of a sample modified with dysprosium, luminescence similar to that of the base alumzirconium oxide system is observed.