A convenient route for the synthesis of complex metal oxides employing solid-solution precursors

Abstract

Synthesis of complex metal oxides by the thermal decomposition of solid-solution precursors (formed by isomorphous compounds of component metals) has been investigated since the method enables mixing of cations on an atomic scale and drastically reduces diffusion distances to a few angstroms. Several interesting oxides such as Ca₂Fe0_3.5, CaCo₂0₄, Ca₂C0₂0₅ and Ca₂FeCo0₅ have been prepared by this technique starting from carbonate solid solutions of the type Ca_1-xFe_xC0₃, Ca_1-xCo_xC0₃, and Ca_1-x-yM_xM'_yC0₃ (M, M' = Mn, Fe, Co). The method has been extended to oxalate solid-solution precursors, and the possibility of making use of other kinds of precursor solid solutions is indicated.