Structural and Magnetic Studies of Al-Doped Y2.8 La0.2 Fe5 O12 Nanoferrites Prepared by a Sol-Gel Route

Abstract

Y3Fe5O12 and Y2.8La0.2Fe5 − xAlxO12 (x = 0.0, 0.1, 0.2, and 0.3) nanoferrites have been prepared by the sol-gel auto combustion route followed by sintering at 900 ° C for 3 h. The garnet phase formation has been confirmed by analyzing XRD patterns and also by noting intense bands for Fe-O vibrations in FTIR spectra. The XRD analysis has shown a decreasing trend for lattice parameter, X-ray density, and d-spacing due to the addition of smaller Al3+ ions at tetrahedral sites. The SEM study has shown agglomerated and branched morphology with an average branch width and branch length ranging between 90–140 nm and 537–437 nm, respectively. Enhanced values of saturation magnetization have been observed for all the samples due to the presence of 6.7% of La3+ ions in place of Y3+ ions. However, it decreased due to weakening of superexchange interaction with the addition of Al3+ ions at tetrahedral sites. These nanoferrite powders can be used as a substitute for costly rare earth garnets and also in many high-frequency microwave devices.