Hard magnetic membrane based on bacterial cellulose - Barium ferrite nanocomposites.

Magnetic membranes based on bacterial cellulose (BC) nanocomposites have been extensively researched. However, most magnetic nanoparticles (NPs) incorporated in the BC matrix were focused on soft magnetic phases, which limited the extensive use of magnetic BC membranes. Therefore, this work proposes a method to fabricate hard magnetic membrane based on the BC matrix and magnetically hard phase barium ferrite (BFO) NPs. The nanocomposites showed the peaked tensile strength and modulus at the low concentration of BFO whereas the magnetization increased drastically with the BFO content. They also demonstrate the high flexibility up on bending and the sensitivity to external magnetic fields. Furthermore, unlike other magnetic BC membranes, the BC/BFO nanocomposites exhibited the hard magnetic properties, i.e. they could retain their magnetic attraction after being magnetized by a permanent magnet. These properties open the possibility to employ these materials in various fields, such as information storage, anti-couterfeit or electromagnetic shieldings.