Controlled synthesis of Fe_3O_4 nanosheets via P123 micelle template

摘要

Magnetic iron oxide nanomaterials (e.g. Fe_3O_4 and γ-Fe_2O_3) with different morphologies have aroused extensive attention due to their fundamental research and potential technological applications such as magnetic recording media, magnetic fluids and magnetic drug-targeting. In this article Fe_3O_4 nanosheets were successfully synthesized using triblock copolymer (PEO)_(20)(PPO)_(70)(PEO)_(20)(P123) micelles as structure-directing agents in the presence of surfactant-assisted cthylene glycol (F.(i) and precipitator hexamethylenetetramine (HMTA) at 70°C for 2 h in N_2. The Fe_3O_4 nanosheets have irregular shape with thickness of the Fe_3O_4 nanosheets about 10-15 nm. The X-ray diffraction (XRD) pattern confirms the Fe_3O_4 nanosheets have magnetite structure and its nine distinguishable diffraction peaks can be perfectly indexed to the (1111),(220), (311), (222), (400), (422), (511), (440), and (533) planes of the fee structure of magnetite. Its saturation magnetization (σ_s) is 58.4 emu/g. The possible formation mechanism of the Fe_3O_4 nanosheets in present work is proposed.