Synthesis, Structure, Magnetic and Absorption Properties of Nd Doped Y<sub>3</sub>Fe<sub>5</sub>O<sub>12</sub> Garnets Prepared by Mechanochemical Method

Abstract

Neodymium substituted yttrium iron garnet (YIG) nanoparticles with compositional variation of NdxY3−xFe5O12 where x = 0.0, 0.2, 0.5 and 0.8 was prepared by mechanochemicals method using high energy milling (HEM). The characterization was done using X-rays diffractometer (XRD), scanning electron microscope (SEM), vibrating sample magnetometer (VSM) and vector network analyzer (VNA). It was found that the mechanical milling followed by sintering promotes the complete structural formation of the yttrium iron garnet (YIG) structure. The XRD patterns confirm the complete introduction of Nd3+ ion into the YIG with an addition of Nd doping concentration. nanocrystalline particles with high purity and sizes ranging from 0.12μm to 0.16μm were obtained. The magnetization value, Ms from all Nd-doped samples were obtained in the range between 34 to 37emu.g-1. The magnetic coercivity (Hc) was achieved of 0.012kOe (12Oe) for the non-doped sample (YNd-0) and then increase with the addition of neodymium concentration. The increase in Hc for all the sample series can be attributed to an enhancement of the magnetocrystalline anisotropy with anisotropic Fe2+. The variation of the reflection loss (RL) versus frequency was observed in Nd doped YIG, Y1-xNdxFe5O12 with x = 0.0 – 0.8 in the frequency range of 7 –12 GHz. The optimum reflection loss (RL) was found to be 8.66(-dB) at 9.5GHz in Y2.2Nd0.8Fe5O12 (YNd-08) for x = 0.8.