Rietveld refinement and structural characterization of Mn0.5Zn0.5La0.09Fe1.91O4 nanocomposite

Abstract

Mn0.5Zn0.5La0.09Fe1.91O4 composite has synthesized by adopting the solid-state reaction method. Chemicals like MnO2, ZnO, Fe2O3 and La2O3 were used for preparation of the powder sample of Mn0.5Zn0.5La0.09Fe1.91O4. As prepared composites were subjected to sintering for 5hrs at the temperature of 850 °C. The obtained sample was structurally characterized using XRD. The crystallite size was calculated using Debye Scherrer formula which came out to be 51.14 nm, 95.21 nm, 52.48 nm for phase A, B and C respectively. Further refinement of the XRD data was performed using Rietveld refinement method by using FullProf Suit. The refinement of XRD data for synthesized sample confirms the presence of three phases: phase A – periclase (Fe0.037Mg0.0963O) 1.7%, phase B – lanthanum (La) 0.3%, phase C – hetaerolite (Mn2O4Zn) 97.9%. The results obtained from XRD suggests that the nanoparticles in phase A are cubic in shape and the no. of space group is obtained as 225 with Laue class and point group m-3m. The Hermann-Mauguin symbol is Fm-3 m. The nanoparticles in phase B are found to be hexagonal in shape with the no. of space group is obtained as 194 with Laue class and point group 6/mmm. The Hermann-Mauguin symbol for phase B is P63/mmc. The XRD studies for phase C showed that it has tetragonal structure. From the Rietveld refinement, the no. of space group is obtained as 141 with Laue class and point group 4/mmm. The Hermann-Mauguin symbol is I 41/amd:1. In this paper the Rietveld refinement parameters like the goodness factor, Bragg R value, Rexp are also given.