Mössbauer spectral analysis and Rietveld structural refinement for cationic distribution of Cr-Co ferrites

Abstract

Sol-gel autocombustion was used to prepare Chromium-substituted Cobalt ferrite nanoparticles with the chemical formulas CoCr${_x}$Fe$_{2-x}$O$_4$, with x (0.1 to 0.5 in steps of 0.1).The samples were systematically examined for providing information related to their structural aspects X-ray diffractometry and energy dispersive spectrometry and for determination of accurate ionic distribution using Mössbauer spectrometry and Rietveld structural refinement. The patterns obtained from the energy dispersive spectra ensure that the elemental concentrations of the samples match well with the ionic proportions set in the empirical formulae. Cationic distributions were first made by Mössbauer spectral analysis using hyperfine fields and then by Rietveld analysis based on integrated intensity ratios and profile matching. The results of the study are explained in terms of the compositional variations, cationic inversion degree associated with the fine particle nature of the materials and the relevant cationic distributions as a result of chromium substituted cobalt ferrite.