The effect of nano-SiO2 on magnetic and dielectric properties of Li–Zn ferrite

Abstract

Abstract Densification, grain growth, magnetic and dielectric properties of sintered Li–Zn ferrite (Li0.3Zn0.4Fe2.3O4) doped with nano silicon dioxide (10 nm) were investigated. The density and microstructural results revealed that increasing the nano-SiO2 content resulted in lower density and higher porosity at sintering temperatures below 1 000 °C, whereas at higher temperatures, this led to higher density and grain growth. In addition, nano-SiO2 content greater than 2 wt.% resulted in more reduction in porosity and had no effect on grain growth. Moreover, the highest density and the maximum induction (B s = 380 mT) were obtained for the sample containing 2 wt.% nano-SiO2 and sintered at 1 100 °C for 1.5 h, in comparison with undoped samples. Furthermore, the variation of magneto-dielectric properties as a function of frequency were explained according to Koop's theory and electron hopping between the Fe+ 2 and Fe+ 3 ions.