Morphology dependence of static magnetic and microwave electromagnetic characteristics of polymorphic Fe3O4 nanomaterials

In the present work, Fe3O4 nanospheres, sponges, and urchins were prepared. Investigation of static magnetic and microwave electromagnetic (EM) characteristics of polymorphic Fe3O4 nanomaterials showed that morphology plays a crucial role in determining the resulting properties. Compared with Fe3O4 nanospheres and urchins, enhanced saturation magnetization and coercivity were observed in Fe3O4 sponges composed of ordered nanofibers. Enhancement of saturation magnetization and coercivity are associated with increased magnetic interactions and shape anisotropy, respectively. The Fe3O4 sponges and urchins produced reflection loss (R-L) values of -35.77 dB at 8.0 GHz and -43.23 dB at 16.8 GHz, respectively. The excellent microwave absorption performance is ascribed to their unique morphologies. Such morphologies resulted in reinforced EM parameters and multiresonant behavior.