New combustion synthesis technique for the production of (In_xGa_1−x)₂O₃ powders: Hydrazine/metal nitrate method

A new low-temperature method to produce (In_xGa_1−x)₂O₃ (x = 0.1, 0.2, and 0.3) powders with high purity, high chemical homogeneity and improved crystallinity in the as-synthesized state has been developed. This procedure produced finely divided powders through an exothermic reaction between the precursors. The process starts with aqueous solutions of In(NO₃)₃ and Ga(NO₃)₃ as the precursors and hydrazine as the (noncarbonaceous) fuel. The combustion reaction occurred when heating the precursors between 150 and 200 °C in a closed vessel filled with an inert gas (Ar), which yields (In_xGa_1−x)₂O₃ directly. These materials were compared with powders prepared by a more typical combustion synthesis reaction between nitrates and a carbonaceous fuel at a higher ignition temperature of 500 °C.