Structural, morphological, spectral, XPS, and dielectric properties of Ba4Co2NdxFe36−xO60 nanocrystalline materials

Neodymium (Nd3+) substituted Ba4Co2NdxFe36-xO60 (0.0 ≤ x ≤ 0.16, Δx = 0.04) hexaferrite materials were produced by self-combustion sol–gel synthesis and sintered at 1200 °C for 6 h in a digitally controlled box furnace. XRD was performed to examine all the specimens for structural examination. XRD spectra confirmed the single-phase development of synthesized materials. Incorporating Nd into structural parameters resulted in an enhancement in lattice parameters (a and c). The fluctuations were also noted in the lattice values of “a" and “c" that are 5.866–5.869 Å and 112.745–112.800 Å. Fourier transform infrared spectroscopy identifies two absorption bands between 507–485 cm−1 and 462–435 cm−1 due to Fe–O stretching vibrations. Epsilometer R60 VNA was used to perform the dielectric measurements from the 1 MHz–6 GHz frequency range. Maxwell–Wagner theory explains the variations in frequency-dependent dielectric parameters well. The value of dielectric loss was decreased at a higher frequency region (6 GHz) for all doped samples. The sample with x = 0.08 shows the maximum Q-value about 17,893 at 0.037 GHz. The impedance study approved the impact of grain and grain boundaries on Cole–Cole graphs. The attenuation/reflection loss factor of the unsubstituted sample has the smallest value of − 44.2 dB at 1.2 GHz, considered the best-absorbing material among all the samples. Scanning electron microscopy gives information about the morphology and approves the hexagonal plate-like shape of grains. X-ray photoelectron spectroscopy confirmed the existence of all metal ions with their required valence states. According to these findings, impedance analysis, Q-value, and reflection loss, the prepared materials are suitable for higher frequency gadgets, including MLCI, microwave absorbers, and dielectric resonators.