Study of Gadolinium Substituted Barium-Based Spinel Ferrites for Microwave Applications

Magnetic nanoparticles, with their remarkable versatility and the promise of widespread applications across numerous fields of industry, have become a focal point of scientific inquiry and exploration. Using the sol–gel approach, in sequence spinel ferrite nanoparticles, BaGd_xFe_2-xO₄(x = 0.0, 0.025, 0.05, 0.075, 0.10), were investigated. The atomic structure of the fabricated samples was examined by SEM, and XRD was used to assess the material. The results of electrical analysis demonstrated a remarkable increase in activation energy and resistivity upon the incorporation of gadolinium (Gd) into the material. With the substitution of Gd³⁺, and as a direct result of this, both the dielectric and complex dielectric constants have seen a considerable decrease, along with a sharp decrease in direct current (DC) resistivity when the temperature rises. The increase in Gd concentration was found to correlate with a reduction in both remnant and saturation magnetization, as well as an increase in coercivity (Hc).The frequency range of 0.5–12 GHz was used for conducting microwave measurements on the spinel ferrite sample. Spinel ferrites exhibit frequency dispersion, which is brought on by domain wall pinning and natural magnetic resonance. These parameters collectively suggest that the manufactured samples could be beneficial for microwave applications.