Effect of aluminum substitution on structural and magnetic properties of yttrium iron garnet nanoparticles prepared by sol-gel method

In this study, aluminum ion (Al3+) substituted yttrium iron garnet nanoparticles Y3AlxFe5-xO12 (x = 0.0, 0.2, 0.4) were fabricated by the sol-gel method. X-ray diffraction (XRD) patterns confirmed the pure garnet structure for all samples. The chemical bonds and the garnet phase were studied by using FT-IR, Far-FTIR. The cation distribution and the magnetic hyperfine parameters were obtained by MÖssbauer spectroscopy and confirmed the VSM results. The results of vibrating sample magnetometer (VSM) show that saturation magnetization decrease with increasing aluminum ion concentration. These changes assigned to the Neel theory and the spin canting due to the reduction of superexchange interactions between iron ions in the octahedral and tetrahedral and octahedral sites.