Effects of ZnO and NiO on material properties of microwave absorptive glass-ceramic tile derived from iron ore tailings

Effects of ZnO and NiO on structural, morphological, magnetic properties and microwave absorption behavior of glass-ceramic tiles derived from iron ore tailings (IOTs) were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), magnetization measurements, fourier transform infrared spectroscopy (FTIR) and complex permittivity and permeability measurements. Gradual replacement of NiO by ZnO was found to lower crystallinity of the glass-ceramic and reduce average grain size of the only crystalline phase indexed as spinel Ni-Zn ferrite. Ni2+ ion oscillations at different coordination environments inside glass network led to several notable dielectric losses in 3.8-15 GHz. Ferromagnetic resonance frequency is positively correlated with the amount of Ni2+. These Ni-related effects enhanced the maximum microwave attenuation of the glass-ceramic to reach −34.35 dB with its frequency being tunable in 6.70-11.20 GHz.