In this research paper, microstructural, electromagnetic properties, and thermal stability, of (Mg0.3Cu0.2Zn0.5O) (Fe2O3) ceramics were adjusted by using low-melting point molybdenum trioxide (MoO3) as additive. The required ferrite powders were synthesized through a cost-effective sol–gel method. The ferrite ceramics with high density and high permeability were prepared, using various content of MoO3 (from 0.00 to 1.00 wt%) at low sintering temperature. Results indicate that MoO3 not only improves density and grain growth of ferrite samples, but also effectively tailors the saturation magnetization (Ms), coercive field strength (Hc), initial permeability (µi), and Curie temperature (TC). For a qualitative comparison, the SEM images of both surface and fracture surface of the specimens were obtained. The results indicate that 0.25 wt% MoO3 can promote grain growth, densification and uniformity, and reduce pores between grains of the sintered sample. In particular, MgCuZn ferrite with high bulk density (ρ = 4.7 g/cm3), high initial permeability (μ′ = 460), high saturation magnetization (Ms = 50.6 emu/g), and low coercivity (Hc = 1.4 Oe) are obtained when the content of additive is 0.25 wt%. However, the excessive amount of MoO3 deteriorates the grain size uniformity and weakens the magnetic properties due to the production of non-magnetic MoO3 liquid phase
