Preparation and characterization of spindle-like Fe(3)O(4 )mesoporous nanoparticles

Magnetic spindle-like Fe(3)O(4 )mesoporous nanoparticles with a length of 200 nm and diameter of 60 nm were successfully synthesized by reducing the spindle-like α-Fe(2)O(3 )NPs which were prepared by forced hydrolysis method. The obtained samples were characterized by transmission electron microscopy, powder X-ray diffraction, attenuated total reflection fourier transform infrared spectroscopy, field emission scanning electron microscopy, vibrating sample magnetometer, and nitrogen adsorption-desorption analysis techniques. The results show that α-Fe(2)O(3 )phase transformed into Fe(3)O(4 )phase after annealing in hydrogen atmosphere at 350°C. The as-prepared spindle-like Fe(3)O(4 )mesoporous NPs possess high Brunauer-Emmett-Teller (BET) surface area up to ca. 7.9 m(2 )g(-1). In addition, the Fe(3)O(4 )NPs present higher saturation magnetization (85.2 emu g(-1)) and excellent magnetic response behaviors, which have great potential applications in magnetic separation technology.