A Facile Solution Combustion and Gel Calcination Process for the Preparation of Magnetic MnFe₂O₄ Nanoparticles

A facile solution combustion and gel calcination process for the preparation of magnetic MnFe²O⁴ nanoparticles was introduced. The experimental results showed that the volume of absolute alcohol and the calcination temperature were two key factors to grain size, crystallinity and magnetic properties of MnFe²O⁴ nanoparticles. With the volume of absolute alcohol increasing from 15 to 100 mL, the average grain size of MnFe²O⁴ nanoparticles calcined at 400 °C for 2 h increased from 13.4 nm to 36.0 nm, and the saturation magnetization (M) value of MnFe²O⁴ nanoparticles increased from 1.2 emu/g to 105.5 emu/g; while, with the calcination temperature increasing from 400 °C to 800 °C, the average grain size increased from 13.4 nm to 32.9 nm, and the saturation magnetization value increased from 1.2 emu/g to 15.3 emu/g. The specific surface area of MnFe²O⁴ nanoparticles calcined at 400 °C for 2 h with absolute alcohol of 30 mL was measured, which was large of 49.6 m²/g.