Synthesis of metastable hard-magnetic ε-Fe₂O₃ nanoparticles from silica-coated akaganeite nanorods

Abstract

We present a simple preparation route to obtain a nanoscale metastable hard-magnetic ε-Fe₂O₃ phase, using silica coated β-FeOOH nanorods as a precursor and an annealing process. The synthesized ε-Fe₂O₃ nanoparticles exhibit large coercivity (H_C ∼ 20 kOe at 300 K and H_C ∼ 1.6 kOe at 400 K), confirming their high potential for practical applications.