Production of Gadolinium Iron Garnet by Anion Resin Exchange Precipitation

Resumo

A new method to synthesize nanosized powders of gadolinium iron garnet was proposed, in which the precipitant is a strong base anion-exchange resin. The effect of the type of the resin (A400 or AV-17-8), the type of its counterion (OH or CO₃), and the temperature and duration of the process on the stoichiometry of the formed product and its yield was studied. The time–temperature parameters of gadolinium iron garnet crystallization were determined. The obtained products were investigated by X-ray powder diffraction analysis, thermal analysis, IR spectroscopy, and electron microscopy. Procedures were developed to produce precursors of stoichiometric composition, which, after annealing at 1000°C, form pure phase Gd₃Fe₅O₁₂ with a particle size of 20–40 nm according to transmission electron microscopy.