Preparation and characterization of α-Fe2O3/Fe3O4 heteroplasmon nanoparticles via the hydrolysis-combustion-calcination process of iron nitrate

In this work, a feasible and facile hydrolysis-combustion-calcination process of ferric nitrate for the preparation of magnetic α-Fe2O3/Fe3O4 heteroplasmon nanoparticles was represented. The influences of hydrolysis time, hydrolysis temperature, Fe3+ concentration, anhydrous ethanol volume, calcination time, and calcination temperature on the properties of α-Fe2O3/Fe3O4 heteroplasmon nanoparticles were investigated. According to a series of characterization analysis, the optimal preparation conditions were confirmed: 0.05 M Fe(NO3)3·9H2O was hydrolyzed at 90 °C for 8 h, and then the precursor was calcined at 200 °C for 2 h with 20 ml anhydrous ethanol. While, the morphology of α-Fe2O3/Fe3O4 heteroplasmon were spherical structures with the average particle size of about 46 nm, and their saturation magnetization was 54 emu g−1. The α-Fe2O3/Fe3O4 heteroplasmon nanoparticles possessed controllable magnetic properties and a more stable state, which suggested promising applications.