Effect of Dy3+ substitution on structural and magnetodielectric properties of Mn–Zn ferrites synthesized by microwave hydrothermal method

• Published in: Journal of materials science. Materials in electronics 2023-03, Vol.34 (8), p.758, Article 758
• Main Authors: Neelima, P., Usha, P., Ramesh, T., Ganta, Kiran Kumar
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Complex permittivity; Dielectric loss; Dielectric properties; Differential thermal analysis; Diffraction patterns; Dysprosium; Electrical properties; Electrical resistivity; Fourier transforms; Frequency ranges; Hysteresis loops; Infrared spectra; Infrared spectroscopy; Magnetic properties; Manganese zinc ferrites; Materials Science; Microwave sintering; Optical and Electronic Materials; Permeability; Permittivity; Sintering (powder metallurgy); Solid phases; Spherical powders; Spinel; Structural analysis; Substitutes; Superhigh frequencies; Synthesis; Zinc ferrites
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-023-10189-0

In this study, dysprosium-substituted Mn–Zn ferrites (Mn 0.6 Zn 0.4 Dy x Fe 2-x O 4 ; where x  = 0, 0.01, 0.03, 0.05, 0.07 and 0.09) were synthesized using the microwave hydrothermal method to examine the effect of Dy 3+ substitution on the structural, electrical and magnetodielectric properties of Mn–Zn ferrites. The structural analysis of the synthesized powders was performed using X-ray diffraction (XRD) patterns and the results show that for lower concentrations of Dy 3+ , the prepared ferrites crystallize in a single spinel phase structure, while a trace of DyFeO 3 appears as a minor phase for higher concentrations. The transmission electron microscopy (TEM) images show that the synthesized powders have a spherical morphology with nano dimensions. The thermogravimetric and differential thermal analysis (TG–DTA) was carried out to investigate the presence of hydrated water and to understand the decomposition behaviour. The synthesized powders were then sintered at 900 °C for 90 min using the microwave sintering method. Fourier transform infrared (FTIR) spectra of the samples confirm the formation of spinel structure. A slight decrease in the low-frequency vibrational band position is observed in IR spectra with Dy 3+ concentration. Studies on electrical properties reveal that the dc resistivity enhances with Dy 3+ substitution and the value of resistivity is in the range of 10 5 –10 7 Ω-cm. The magnetic hysteresis loops of all the samples reveal the soft magnetic nature. The magnetic properties of Mn–Zn ferrite changed with Dy 3+ substitution due to interactions between Dy 3+ (4f 9 ) and Fe 3+ (3d 5 ) ions. The magnetodielectric properties were measured as complex permeability and complex permittivity over an X-band frequency range. The frequency-dependent magnetodielectric properties change significantly with the amount of Dy 3+ present. The change in dielectric properties is significant as compared to magnetic properties with the Dy 3+ concentration. At 8.2 GHz, the real part of permittivity decreases from 3.6 to 1.7, while the real part of permeability maximum and minimum values are in the range of 0.7 to 1.21. From magnetodielectric properties, it can be observed that the dielectric loss (ε″) decreases with Dy 3+ addition and magnetic loss (μ″) increases gradually, which makes the difference between ε″ and μ″ reduce, thereby improving the impedance match. The obtained result suggests that Dy 3+ substitution can be used to tune the electrical and ma