Dependence on cation distribution of particle size, lattice parameter, and magnetic properties in nanosize Mn–Zn ferrite

Abstract

In Mn1−xZnxFe2O4 (x=0 to 1) nanosize particles prepared through hydrothermal precipitation we observe a decrease in particle size from 13 to 4 nm with increasing Zn concentration from 0 to 1. The lattice constant, a, for all Mn/Zn concentrations is found to be less than that for the corresponding bulk values. At specific compositions within x=0.35 and 0.5, the temperature dependence of the magnetization exhibits a cusp-like behavior below the temperature at which the nanoparticles undergo a ferri- to para-magnetic transition (Tc). The Curie temperatures, Tc, of the nanoparticles are in the range of 175–500 °C, which are much higher than their corresponding bulk values. To explain these unusual features, the strong preferential occupancy of cations in chemically inequivalent A and B sites and the metastable cation distribution in nanoparticles are invoked.

Effects of Li2O additive on structural, magnetic and electrical properties of Ni-Mg ferrite

“…The patterns clearly show the formation of spinel structure for all samples and indicated that these materials have a well-defined single crystalline phase. By analyzing the XRD patterns it was observed that the peaks (220), (311), (222), (400), (511) and (440) comply with the reported value (Khan et al 2013, Rath et al 2002 and no traces of raw materials are found, thereby confirming that the chemical reaction is completed. lattice parameters were determined.…”

Synthesis and characterization of manganese–zinc ferrite obtained by thermal decomposition from organic precursors

“…However, as in the case of the combustion method, unstable powders, forming hard agglomerates, can be obtained [23]. Because of their unstable character, foreign nonmagnetic phases (e.g., hematite: Fe 2 O 3 ) may occur as a result of the further thermal treatment [24,25].…”

Synthesis of Mn Zn Ferrites by Oxide and Wet Chemical Methods

“…The value of Tc is found to be higher in the case of the ultrafine powder than that in bulk ferrites. This is due to the deviation of cation distribution in a nano-sized particle as in comparison with its bulk counterparts as reported [17]. Licensed Under Creative Commons Attribution CC BY a marginally higher value of Curie temperature than that of the ferrite samples prepared by oxide method.…”