Preparation and Characteristics of Nanocrystalline Yttria by Microwave-Induced Solution Combustion Method

Nanocrystalline yttria powders were successfully synthesized by microwave-induced solution combustion method using a binary yttrium salt system with yttrium nitrate as oxidant and yttrium acetate as reductant. The process involved the redox reaction between the two yttrium salt under the heat generated by absorbing microwaves. The prepared powders were characterized by X-ray diffraction (XRD), Fourier Transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) to study the structure and powder morphology. The prepared powders were indicated to exhibit single-phase cubic crystalline yttria structure. The oxidant/reductant ratios and the calcination temperatures had an effect upon the particle size and powder morphology. The size of the crystallites varied in the range of 16 nm~27 nm with different reductant proportion. The powders were observed to show loosely agglomerated fractals.

Nanoscopic yttrium oxide fluorides: non-aqueous fluorolytic sol–gel synthesis and structural insights by 19F and 89Y MAS NMR

Nanoscopic yttrium acetate fluorides Y(CH3COO)3−zFz and yttrium oxide fluorides YO(3−z)/2Fz were prepared via the fluorolytic sol–gel route and studied by 19F and 89Y MAS NMR.

Glycothermal Synthesis and Magnetic Properties of YIG/YAG Nanoparticles

Yttrium aluminum garnet (YAG) nanoparticles of 14.5±3.2 nm in diameter are synthesized from yttrium acetate and aluminum isopropoxide in 1,4-butanediol by autoclave treatment at 300oC for 2h. Yttrium iron garnet (YIG) / YAG composite nanoparticles of 21.1±4.9 nm in diameter are synthesized from yttrium acetate and iron(III) acetylacetonate in 1,4-butanediol by autoclave treatment at 300oC for 2h using YAG nanoparticles as the seed. In contrast, YIG is not formed by the same procedure in the absence of the YAG seed. The saturation magnetizations of nanoparticles with different YIG/YAG ratios range from 11.9 to 17.8 emu/g. YIG/YAG nanoparticles dispersed in the agarose gel are observed by magnetic resonance imaging (MRI). The degree of the negative MRI contrast depends on the concentration of YIG/YAG nanoparticles.