Slepets A. Synthesis and physico-chemical properties of isomorphically substituted ortovannadats of rare earth elements

The dissertation is devoted to the improvement of methods of synthesis ortovanadats rare earth elements, as well as the establishment of interconnections in the system of synthesis - structure - properties. The paper describes in detail the optimized method for the synthesis of new complex oxide materials of the type (La, Eu, Er, Sm) - (Ca) -V-O based on matrix ortovannadate. Using three synthesis methods: solid-phase method, precipitation and sol-gel method, a series of compounds was obtained: R1-xCaxVO4-δ 0  x  0.2, R = La, Eu;, La1-xRxVO4 0  x  0.2, R = Eu, Sm; La1 x yRyCaxVO4-δ (0 ≤ x, y ≤ 0.2), R = Eu, Sm; La1 xEu1/4xEr1/4xCa1/2xVO4-δ (0 ≤ x ≤ 0,2). The processes of phase formation have been studied and the areas of homogeneity of the synthesized materials have been determined. The regularities of the influence of the nature of the substituents on the structure of the synthesized substances have been established and features of the physicochemical properties of substituted ortovannadats of rare-earth elements, in particular their luminescent and catalytic properties, have been investigated.