Yttrium-substituted Co0.5Ni0.5YxFe2-xO4 ferrites as microwave absorbers by investigating structural, magnetic, dielectric, and absorption characteristics

• Published in: Journal of magnetism and magnetic materials 2023-04, Vol.572, p.170646, Article 170646
• Main Authors: Teber, Ahmet, Sarac, Mehmet F.
• Format: Article
• Language: English
• Subjects: Ferrites; Hydrothermal method; Microwave absorber; Nanostructures; Yttrium substitution
• ISSN: 0304-8853
• DOI: 10.1016/j.jmmm.2023.170646

•• Yttrium-substituted Co-Fi ferrites synthesized by hydrothermal method caused changes in dielectric, magnetic, morphological, and structural properties.•• FT-IR results indicate the presence of the predicted spectrum of absorption bands confirms the creation of the spinel structure.•• SEM show a relatively small spherical structures of Ni-Co ferrites particles can be seen to change from spherical to hexagonal-shaped with increasing Yttrium concentration.•• The results of Hc obtained exhibit a slight increase of the porosity with the increase of Y- content.•• The drop of Hc with increasing porosity means that a less demagnetizing field is required for the magnetization to be lost because of the presence of pores.•• The minimum RL value and bandwidth vary significantly with the amount of Yttrium in the mixture. The effect of Yttrium Substitution on Co0.5Ni0.5YxFe2- xO4 (0.0 ≤ x ≤ 1.0) Ferrites as Microwave Absorbers was investigated to include structural, magnetic, dielectric and X-band absorption properties. The main objective of this work is to enhance microwave absorption properties of materials with interesting dielectric/magnetic behaviors by doping rare earth element of Yttrium based on transition metals. The hydrothermal method was used to create Yttrium (Y) substituted nanoparticles, and the effects of Y-ion substitution on the characteristics, structural, magnetic features were examined by XRD, FT-IR, SEM-EDS, TEM-SAED, and VSM, respectively. Electromagnetic properties were obtained from microwave scattering parameters measured via a metal-backed transmission line and Nicholson-Ross Weir techniques using a vector network analyzer (VNA) in conjunction with an X-band waveguide set. Return loss (RL) values of the samples were obtained from the electromagnetic constitutive parameters (permittivity and permeability). According to the XRD measurements, hexagonal crystal structure of ferrite and YFeO3 as secondary phase nanocrystal sizes are between 11 and 67 nm. Refined structural parameters using Rietveld analysis are carried out using the TOPAS refinement program. A good match was observed between the diffraction patterns obtained and calculated by Rietveld analysis. Moreover, the morphological analyses indicate that the relatively small spherical structures of Ni-Co ferrites particles can be seen to change from spherical to hexagonal-shaped with increasing yttrium concentration. The results of the FT-IR study show that the spinel structure has formed