Abstract
Magnetite (Fe
3O
4) nanowires with diameters around 25
nm and lengths up to 1.5
μm have been successfully synthesized using a simple polyethylene glycol (PEG)-assisted hydrothermal technique. Powder X-ray diffraction pattern, energy-dispersive X-ray spectroscopy, and selected-area electron diffraction measurements indicated that the as-synthesized product is pure single-phase Fe
3O
4 with a good crystalline state. The size, morphology, and structural features of the as-prepared Fe
3O
4 were investigated by transmission electron microscopy and scanning electron microscopy. Effects of reaction-controlling parameters such as the volume ratio of PEG to water, operating temperature, and duration of process have been investigated in detail. Vibrating sample magnetometer measurements show that Fe
3O
4 nanowires exhibit a ferrimagnetic behavior at room temperature; a saturation magnetization of 90.94
emu/g is obtained, which is essentially higher than the reported values. A reaction mechanism for the nanowire formation is also proposed.