Structure and magnetic properties of SiO2-FeO-CaO-Na2O bioactive glass-ceramic system for magnetic fluid hyperthermia application.

Ferrimagnetic glass-ceramics comprising maghemite crystals were synthesized for magnetic fluid hyperthermia (MFH) usage. The present work is focused on the result of the chemical composition and heat treatment temperature on the magnetic behavior of (60-x)SiO2-(10+x)FeO-20CaO-10Na2O,0≤x≤30 glass-ceramic system. It was observed that with the increasing of FeO from 10 to 40 wt% in the glass-ceramic compound, the percentage of maghemite phase increased. It was also seen that in the low heat treatment temperature (680 °C), by adding iron oxide up to 30 wt%, iron cations acts as a network former, and more than this amount acts as a network modifier. In contrast, iron cations in the same composition range at high temperatures (840 °C), acts as a network modifier. According to the VSM results, the maximum magnetization of glass-ceramics incremented from 0.23 emu/g to 0.30 emu/g with the increase in FeO percentage. It was also observed that with the increment of iron oxide percentage, the morphology of maghemite crystals changed from spherical to dumbbell-shaped.