Conventional sintering-induced microstructure evolution and transport properties in Ni–Zn soft ferrite

This study investigates the effect of conventional sintering on the microstructure evolution and transport properties, along with optical analysis of Ni-Zn soft ferrite (Ni 0.5 Zn 0.5 Fe 2 O 4 ) synthesized via the sol–gel route. Ferrite samples were prepared at varied sintering temperatures (Tₛ) ranging from 400 to 1200 °C. X-ray diffraction (XRD) analysis confirmed that higher sintering temperatures improved crystallinity, with the 1200 °C sample exhibiting sharp, narrow peaks indicative of superior crystalline structure, while the 400 °C sample showed broader peaks corresponding to poorer crystallinity. Dynamic light scattering (DLS) results further validated the reduction of agglomeration and increase in particle density at 1200 °C. SEM shows increased grain size. Optical characterization done through UV–Vis, DLS, and FTIR for correlating structure evolution with respect to Tₛ. Tauc plot reveals optical bandgap widening from 3.9 to 5.1 eV with respect to elevated Ts. Electrical behavior, studied via impedance spectroscopy, demonstrated enhanced performance at higher sintering temperatures. Magnetic analysis showed that permeability remained stable up to 3 MHz before gradually decreasing, while the imaginary component of permeability dropped sharply with frequency. The T s = 1200 °C sample exhibited 8 times improved permeability with a broad utility zone. These findings provide insights into optimizing sintering conditions to achieve targeted structural and functional properties of Ni–Zn ferrite for future device applications.