Magnetic properties of PAN-based carbon fibres modified with magnetite nanoparticles Original Research Article

The magnetic properties of PAN-based carbon fibres modified with magnetite nanoparticles are presented and analyzed. PAN fibres and PAN-based carbon fibres modified with different amounts of magnetite are characterized by the use of magnetization measurements and Mössbauer spectroscopy techniques. The investigations revealed that magnetite (Fe3O4) decomposed into Feα, Feγ and cementite (Fe3C). Precise analysis of the phase’s contents for different carbon fibres has been carried out in relation to the initial magnetite compound. Analysis of the Mössbauer spectra allowed the determination of the phase contents in fibres with different initial magnetite concentrations. Partial transformation of magnetite into γ-Fe induces catalytic carbonization and formation of a highly crystalline carbon matrix at 1000 °C. The apparent crystallite size in carbon fibres containing 30% magnetite was almost seven times higher than that found in the pure carbon fibres.