Impact of erbium substitution on structural, dielectric, spectral, and microwave absorption properties of Ba3Co2Fe24O41 Z-type hexa-ferrites for microwave devices applications

A series of erbium-substituted Z-type hexaferrites with composition Ba(3)Co(2)ErxFe(24-x)O(41) (0.00 <= x <= 0.12, Delta x = 0.03) was synthesized via the sol-gel auto combustion technique and sintered at 1200 degrees C for 5:30 h. XRD analysis confirmed the single phase crystals throughout the samples. Incorporating erbium ions into a Z-type hexagonal lattice showed improved structural parameters. The lattice parameters (a, c) exhibited an increasing trend with the rare earth (Erbium) substitution in the range of 5.884-5.891 nm and 52.561-52.770 nm. Scherrer's equation was used to find crystallite size in 28-30 nm range. Absorption bands of ferrite phase were confirmed by Fourier Transform Infrared Spectroscopy. Dielectric characteristics of synthesized materials were studied through Epsilometer R60 VNA over a frequency 1 MHz to 6 GHz range. Variations in dielectric parameters were observed by substituting erbium ion into a Z-type hexaferrite lattice. The magnitude of the dielectric constant, AC con-ductivity, tangent loss, and dielectric loss increases at higher frequencies. While, dielectric constant, AC con-ductivity, loss factor, and tangent loss decrease with Erbium substitution. The high value of Q-factor similar to 10232 at 0.87 GHz was observed. The cole-cole plots in impedance analysis confirmed the character of grains and grain boundaries in the conduction mechanism. Minimum reflection loss (RL) was-67 dB for the sample x = 0.06 at 0.2 GHz. At 1.28 GHz frequency, RL = -46 dB was observed for sample x = 0.03. The morphological study (SEM) revealed the hexagonal platelet-type grains with an average grain size of 2.48-2.73 & mu;m. Minimum reflection loss, small crystallite size <50 nm, and high-quality factor suggested that these materials are suitable candidates for microwave absorbers, resonant circuits, multi-layer chip inductors, and high-frequency devices.