Effect of temperature on the preparation of yttrium oxide in microwave field

High-purity yttrium oxide (Y2O3) powder is successfully prepared by microwave-assisted calcination of yttrium oxalate. The decomposition process of yttrium oxalate was analyzed by TG-DSC indicate formation of Y2O3 undergoes three stages. The X-ray diffraction (XRD) analysis indicates that there is no peak of yttrium oxalate hydrate (Y-2(C2O4)(3)center dot 10H(2)O) after microwave-assisted calcination at 600 degrees C for 2 h, with the formation of cubic crystalline Y2O3 structure. Fourier transformed infrared spectroscopy (FT-IR) analysis show similar results with emergence of Y2O3 after calcination at 600 degrees C for 2 h. The precursor had a median particle size diameter 30.719 mu m, while that of all the calcined powders at different temperatures significantly decreased to about 4 mu m. Scanning electron microscopy (SEM) observations demonstrate the morphologies of the precursor and product, and the calcined Y2O3 preserved the amorphous character of the precursor, with rod-like shape. All the TG-DSC, XRD, FT-IR and SEM were utilized to understand the molecular changes in the process of microwave-assisted calcination of Y-2(C2O4)(3) to Y2O3. (C) 2018 Elsevier B.V. All rights reserved.