Mechanochemical Synthesis of Lithium-Niobate-Doped Copper Oxide

Abstract

It is demonstrated by means of XRD, IR spectroscopy, electron microscopy, laser light scattering and measurements of the specific surface area that mechanical activation of a mixture of lithium carbonate, niobium pentoxide and copper oxide in the planetary centrifugal activator AGO-2 involves mixing, dispersion and amorphization of the components, as well as the phase transition of the monoclinic form of niobium (V) oxide into its orthorhombic form. Subsequent mechanical treatment results in the partial formation of a lithium-niobate phase. Thermal treatment of the compacts prepared from mechanically activated powders, at a temperature above 400°C, leads to the appearance of the structure-forming trigonal phase based on LiNbO₃. The data obtained provide evidence that the mechanochemical method is promising for the synthesis of solid solutions based on lithium niobate.