Magnetic and dielectric properties of rare earth substituted Ni0.5Zn0.5Fe1.95R0.05O4 (R = Pr, Sm and La) ferrite nanoparticles

Abstract Ni 0.5 Zn 0.5 Fe 1.95 R 0.05 O 4 nanoparticles (R = Pr, Sm and La) have been synthesized by citrate precursor method and annealed at 450 °C. All the samples were found to be in single phase. The lattice constants and crystallite size decreases with rare earth substitution (25 nm, 23 nm, 11 nm and 9 nm) due to strain produced in spinel lattice. Saturation magnetization and coercivity of ferrite significantly decreases (50.69 emu/g, 32.17 emu/g. 30.21 emu/g and 34.65 emu/g respectively) with rare earth substitution. The substitution of large ionic radius rare earth ions in Ni 0.5 Zn 0.5 Fe 2 O 4 results in distortion and induces a softening of magnetic exchange interaction. The dielectric measurements at higher frequency range (100 Hz–1 MHz) shows that these substituted ferrites exhibits low dielectric loss, which is suitable for high frequency applications.