Another alternative to the solid state reaction method to synthesize nanocrystalline YIG: Ammonium nitrate melt technique

The structural and magnetic properties of yttrium iron garnet particles, synthesized in an ammonium nitrate melt (ANM), were investigated by magnetization measurements, XRD analysis and SEM microscopy and compared with that of the samples prepared using a solid state reaction (SSR) route. The phase formation of YIG starts at lower temperatures with the ANM technique and then develops with increasing temperature and sintering time. An almost single-phase sample was obtained by annealing for 2 hours at 1300 deg. C, after which the YIG fraction in the SSR sample was only 0.34. Similarly, saturation magnetization of the samples sintered in the same conditions is always higher in the samples sintered via the ANM technique. SEM micrographs were used to determine particle sizes of the ANM samples which vary from the sub-micron to the micron range depending on the sintering temperature. These samples have uniform structures, small grains, better magnetic properties and do not contain massive agglomerates. As a result, the synthesis of YIG via the ANM technique represents another alternative to the SSR route.