SYNTHESIS AND CHARACTERIZATION OF GADOLINIUM GAL-LATE PEROVSKITE STRUCTURE

JZSKAR

Abstract

Complex oxides, especially compounds with a layered structure, are the object of close attention of researchers. Particular attention is due to the presence of unusual electrical, magnetic, and optical properties. Promising materials include lanthanide gallates, in particular gadolinium gallate. Their synthesis is multistage. It flows at high temperatures.In the process of synthesis, mechanical activation of reagents is used, as well as repeated grinding of products followed by annealing.At the same time, most of the work is devoted to obtaining garnet-like structures.The synthesis and study of complex oxides with the perovskite structure are limited.Gadolinium gallate of the composition GdGaO₃ with a perovskite structure was synthesized by ammonium hydroxide coprecipitation from a nitric acid solution of gadolinium and gallium nitrates followed by annealing of the products. The mixture of precipitates of hydrated gadolinium and gallium oxides Gd₂O₃∙nH₂O and Ga₂O₃∙nH₂О formed after the addition of an ammonia solution to the initial solution of metal nitrates was dried at a temperature of 105 °C for 3 hours and calcined at a temperature of 850 °C for 30 hours.The temperature parameters of the synthesis were determined from the results of thermal analysis.Changes in the composition of the mixtures after the synthesis were confirmed by IR spectroscopy.The analysis of IR spectra showed the formation of products that do not contain starting substances.The interaction products were identified by X-ray phase analysis. The formation in the system of hexagonal gadolinium gallate GdGaO₃, which belongs to the GdFeO₃ structural type, with the crystal lattice parameters a = b = 3,777 Å, c = 10,770 Å.