Magnetic properties and BSA adsorption of nano-Fe-embedded BaFe12O19 porous microfibers via organic gel-thermal selective reduction process

Magnetic nano-Fe-embedded BaFe12O19 (NFEB) porous microfibers with diameters about 1-5 mu m were prepared by the organic gel-thermal selective reduction process. The NFEB porous microfibers were formed after reduction of the precursor Fe2O3-BaFe12O19 microfibers at 350 A degrees C for 1 h. The precursor Fe2O3-BaFe12O19 microfibers were obtained by calcination of the gel fibers. In the NFEB porous microfibers, the cubic alpha-Fe particles with size about 300 nm are homogeneously embedded in the hexagonal plate-like barium ferrite and the pore sizes are around 50-150 nm. The magnetic properties of these NFEB porous microfibers are influenced by the mass ratio of alpha-Fe/BaFe12O19 and reduction conditions. The NFEB porous microfibers with the designed soft (alpha-Fe)/hard (BaFe12O19) mass ratio of 1/2 obtained at 375 A degrees C for 1 h have the enhanced saturation magnetization (M (sh) ) of 73.9 Am-2 kg(-1), coercivity (H (c) ) of 81.6 kAm(-1) and remanence (M (r) ) of 34.2 Am-2 kg(-1), compared to the single phase of BaFe12O19 and alpha-Fe microfibers. This enhanced magnetic properties can be attributed to the exchange-coupling interactions. The NFEB porous microfibers exhibit a higher BSA adsorption capability than each single phase of alpha-Fe microfibers and BaFe12O19 microfibers. The BSA adsorption is analyzed.