Abstract
This paper presents the influence of Mn2+ substitution by Ni2+ on the structural, morphological and magnetic properties of Mn1−xNixFe2O4@SiO2 (x = 0, 0.25, 0.50, 0.75, 1.00) nanocomposites (NCs) obtained by a modified sol-gel method. The Fourier transform infrared spectra confirm the formation of a SiO2 matrix and ferrite, while the X-ray diffraction patterns show the presence of poorly crystalline ferrite at low annealing temperatures and highly crystalline mixed cubic spinel ferrite accompanied by secondary phases at high annealing temperatures. The lattice parameters gradually decrease, while the crystallite size, volume, and X-ray density of Mn1−xNixFe2O4@SiO2 NCs increase with increasing Ni content and follow Vegard’s law. The saturation magnetization, remanent magnetization, squareness, magnetic moment per formula unit, and anisotropy constant increase, while the coercivity decreases with increasing Ni content. These parameters are larger for the samples with the same chemical formula, annealed at higher temperatures. The NCs with high Ni content show superparamagnetic-like behavior, while the NCs with high Mn content display paramagnetic behavior.
Highlights
The objective of the study was to investigate the effect of Ni content and annealing temperature on the structure, morphology, and magnetic behavior of Mn1−x Nix Fe2 O4 @SiO2
At 400 ◦ C, the baseline noise and the amorphous halo between 10 and 30◦ (2θ) indicate the formation of poorly crystalized ferrite, while at higher annealing temperatures, the formation of highly crystalline mixed spinel ferrites is confirmed by the sharp diffraction peaks
atomic force microscopy (AFM) investigations revealed round-shaped nanoparticles with sizes depending on the annealing temperature and Ni content
Summary
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. Nanoscale materials have remarkable optical, magnetic, electrical, and catalytic properties [1–6]. The structure and composition of spinel nano-ferrites control the functional properties of magnetic nanosized materials [4,5]. Nanocomposites (NCs) are mixtures of different components at the nanometer scale, with properties that depend on the contribution of each component in the mixture [5]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
