Templated synthesis of highly ordered mesoporous cobalt ferrite and its microwave absorption properties

Based on the nanocasting strategy, highly ordered mesoporous CoFe₂O₄ is synthesized via the‘two-solvent’impregnation method using a mesoporous SBA-15 template. An ordered two-dimensional (P6mm) structure is preserved for the CoFe₂O₄/SBA-15 composite after the nanocasting. After the SBA-15 template is dissolved by NaOH solution, a mesoporous structure composed of aligned nanoparticles can be obtained, and the P6mm structure of the parent SBA-15 is preserved. With a high specific surface area (above 90 m²/g) and ferromagnetic behavior, the obtained material shows potential in light weight microwave absorption application. The minimum reflection loss (RL) can reach -18 dB at about 16 GHz with a thickness of 2 mm and the corresponding absorption bandwidth is 4.5 GHz.