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Updated: May 9, 2026
08:59
Fabrication of a Functionalized Magnetic Bacterial Nanocellulose with Iron Oxide Nanoparticles
Published on: May 26, 2016
Flexible magnetic membranes based on bacterial cellulose and its evaluation as electromagnetic interference shielding
Jéssica A Marins1, Bluma G Soares, Hernane S Barud
1Universidade Federal do Rio de Janeiro/ Instituto de Macromoléculas, Centro de Tecnologia, Rio de Janeiro, RJ, Brazil. Jessica.amarins@gmail.com
Summary
Flexible magnetic membranes were created using bacterial cellulose and magnetite nanoparticles. These novel materials show promise for microwave absorption applications due to their magnetic and electrical properties.
Area of Science:
- Materials Science
- Nanotechnology
- Biomaterials Engineering
Background:
- Bacterial cellulose (BC) offers a unique nanofibrous scaffold for material functionalization.
- Developing flexible magnetic materials is crucial for advanced electronic applications.
- Magnetite (Fe3O4) nanoparticles possess desirable magnetic properties for various uses.
Purpose of the Study:
- To synthesize flexible magnetic membranes with a high content of magnetite nanoparticles integrated into a bacterial cellulose matrix.
- To characterize the structural, magnetic, and microwave properties of the prepared membranes.
- To evaluate the potential of these magnetic membranes as microwave absorber materials.
Main Methods:
- Preparation of bacterial cellulose pellicles followed by impregnation with ferric chloride.
- In-situ magnetite precipitation using sodium bisulfite and alkaline treatment.
- Characterization using Raman spectroscopy, FTIR, XRD, vibrating magnetometer, FEG-SEM, and impedance spectroscopy.
- Investigation of microwave properties in the X-band.
Main Results:
- Successfully prepared flexible magnetic membranes with up to 75% magnetite by weight.
- FEG-SEM confirmed effective coverage of BC nanofibers by well-adhered Fe3O4 nanoparticle aggregates.
- XRD analysis indicated average magnetite crystal sizes of 10-13 nm.
- Magnetic measurements revealed superparamagnetic behavior with high saturation magnetization (60 emu/g) and low coercivity (15 Oe).
- The membranes exhibited high electrical permittivity.
Conclusions:
- Flexible magnetic membranes with significant magnetite content were efficiently fabricated using a bacterial cellulose scaffold.
- The synthesized materials demonstrate excellent magnetic properties and high electrical permittivity.
- These findings highlight the potential of these magnetic BC membranes for application as effective microwave absorbers.
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