Microwave-assisted rapid synthesis of yttrium iron garnet nano powders: formation mechanism and magnetic properties

Abstract

Microwave heat treatment has been employed instead of conventional heat treatment to rapidly synthesize yttrium iron garnet (YIG) nano powders based on chemical co-precipitation technique. Pure phase YIG powders can be formed in a short time, only 2 min with microwave heating temperatures above 850^oC. As the microwave heating time was 10 min, the average particle size increased from about 34 to 88 nm. Owing to the microwave activation, the surface magnetic disordered phase content decreased and the powders achieved a high saturation magnetization of 30 emu/g. Taking advantages of microwave heating, the nucleation of YIG is promoted, and owing to the activated diffusion and chemical reactions in the precursor powders, the uniform growth of YIG particles is established. All these make contributions to the rapid formation of high-quality YIG nano powders.