Magnetic iron nanoparticles prepared by solution combustion synthesis and hydrogen reduction

Highlights: • A method has been proposed to prepare iron nanoparticles by SCS and HR. • A porous α-Fe₂O₃ precursor was fabricated by SCS. • Iron nanoparticles were successfully obtained by HR of the precursor. • The precursor has completed the reduction reaction at 275 °C. A facile and efficient method has been proposed to prepare iron nanoparticles by combining solution combustion synthesis and hydrogen reduction for the first time. A porous α-Fe₂O₃ precursor with high specific surface area of 75 m²/g was fabricated by solution combustion synthesis, and then iron nanoparticles with high saturation magnetization of 196.3 emu/g were successfully obtained by hydrogen reduction of the as-synthesized precursor. With the reduction temperature rising from 275 °C to 600 °C, the saturation magnetization of the products increases from 196.3 emu/g to 209.7 emu/g, whilst the coercivity decreases from 611.4 Oe to 98.8 Oe.