Paweł Kochmański

The main objective of this work was to experimentally confirm that a continuous, substitutional solid solution of a general formula Y1−xYbxVO4 is formed in the pseudo-binary system YVO4–YbVO4, and to investigate its basic unknown properties as a function of composition for 0.00 < x < 1.00. To date, such a solid solution has been obtained and characterized to a limited extent, but only for a few selected compositions. This solution was obtained by a high temperature and, for the first time, using mechanochemical methods. For the solution obtained by the high-energy ball-milling method, unknown physicochemical properties were established over its entire range of homogeneity. The solution was synthesized from mixtures of yttrium orthovanadate (V) with ytterbium (III) orthovanadate (V) of different compositions and investigated by XRD, IR, SEM, and UV-Vis(DRS) methods. It was found that Y1−xYbxVO4 crystallizes in a tetragonal system. The results confirmed that the solid solution Y1−xYbxVO4 has a structure of YVO4 and YbVO4, and its structure is composed of YbO6 and YO6 octahedrons and VO4 tetrahedrons. Moreover, if the parameter (x) in the solid solution Y1−xYbxVO4 increases, its crystalline lattice contracts and the value of the energy gap decreases. This solid solution is stable in the air atmosphere at least up to ~1500 °C. The estimated band gap for this solid solution indicates that it belongs to the semiconductors.