Effect of annealing on properties of Mg doped Zn-ferrite nanoparticles

Abstract

A comparison of structural and magnetic properties of as-prepared and annealed (900 1C) Mg doped Zn ferrite nanoparticles (Zn 1 À x Mg x Fe 2 O 4 , with x ¼0, 0.1, 0.2, 0.3, 0.4 and 0.5) is presented. X-ray diffraction (XRD) studies confirmed the cubic spinel structure for both the as-prepared and annealed nanoparticles. The average crystallite size and lattice parameter were increased by annealing. Scanning electron microscopy (SEM) images also showed that the average particle size increased after annealing. Fourier transform infrared spectroscopy (FTIR) also confirmed the spinel structure for both series of nanoparticles. For both annealed and as-prepared nanoparticles, the O-M tet. -O vibrational band shifts towards higher wave numbers with increased Mg concentration due to cationic rearrangement on the lattice sites. Magnetization studies revealed an anomalous decreasing magnetization for the annealed nanoparticles which is also ascribed to cationic rearrangement on the lattice sites after annealing. The measurement of coercivity showed a decreasing trend by annealing due to the increased nanoparticle size and better crystallinity.

Preparation of Zinc Ferrite by Solid State Method and Its Characterizations

“…[ 29,30 ] The vibration of the unit cell of the cubic spinel can be constructed in the tetrahedral and octahedral sites. [ 31,32 ]…”

Polyol-Mediated Coprecipitation and Aminosilane Grafting of Superparamagnetic, Spinel ZnFe2O4 Nanoparticles for Room-Temperature Ethanol Sensors

“…75 However, the reason for higher magnetization of tt-ZnFe 2 O 4 nanoparticles can be the absence of adsorbed organic species such as oxidized TEG products, high purity, reduced surface disorder, and better crystallinity, which means that tt-ZnFe 2 O 4 nanoparticles behave like pure ferromagnetic material and give rise to higher magnetization. 76 On the other hand, the higher magnetization of sm-ZnFe 2 O 4 nanoparticles is attributed to their smaller size and higher surface area. The morphological homogeneity of sm-ZnFe 2 O 4 nanoparticles is also reflected by the reduced noise of M-H loop.…”

Study of the Dielectric Behaviour of Cr-Doped Zinc Nano Ferrites Synthesized by Sol-Gel Method

“…porosity, grain boundaries, micro-cracks, random crystal orientations, and impurities, etc. It is evident from the previous studies [7] that the losses in sintered polycrystalline ceramics are greatly affected by these extrinsic factors. All these parameters can play a key role in the modification of the dielectric behavior of spinel ferrites which can be more useful for the desired applications.…”