Chemical and Phase Transformations during the Synthesis of Cs[MgR0.5P1.5O6] (R = B, Al, Fe) Complex Oxides from Metal Nitrates

Abstract

Cesium-containing complex oxides Cs[MgR_0.5P_1.5O₆], where R = B, Al, or Fe, were prepared from solutions containing H₃BO₃, metal nitrates, and H₃PO₄/NH₄H₂PO₄. The chemical and phase transformations occurring during the synthesis of these oxides were elucidated by differential thermal analysis (DTA) and X-ray powder diffraction (XRD. Optimal synthesis parameters were found. The boron compound was found to be formed at 800°C, and the aluminum and iron compounds, at 1200°C. All compounds have the pollucite structure (cubic system, space group I4₁32). A comparative analysis of the synthesis of complex oxides under study from various precursors that differed from one another in metal and phosphorus chemical species was carried out.