Template synthesis of ε-Fe2O3 nanoparticles in opal-like matrices

Nanoparticles of ε-Fe₂O₃ were obtained by template synthesis in the pores of opal-like matrices. The maximum content of ε-Fe₂O₃ is achieved upon calcination at 1000 °C for 2–4 h. The content of ε-Fe₂O₃ in a mixture of modifications of iron oxides reaches 80–90%, which is confirmed by the data of X-ray diffraction analysis, Mössbauer spectroscopy and magnetometry experiments.