【摘要】 以淀粉为碳源,通过热解炭化铁/淀粉复合物,成功制备出碳包覆铁(Fe@C)纳米胶囊。在这一过程中淀粉有双重作用,既是碳源又是铁纳米颗粒的稳定剂。采用透射电镜、X射线衍射及振动样品磁强计研究了(Fe@C)纳米胶囊的结构和磁学性能。发现Fe@C纳米胶囊具有完美的铁核(bcc-Fe)/碳壳(石墨层片)包覆结构,其尺寸介于30nm~40nm之间;Fe@C纳米胶囊在室温下有低的剩磁比(Mr/Ms=0.11),表明它在室温下具有超顺磁性。更多还原

【Abstract】 Carbon encapsulated iron(Fe@C) nanocapsules were successfully prepared by pyrolyzing iron/starch composites under mild conditions,in which starch functioned as carbon precursor and stabilizer for iron nanoparticles.The as-obtained Fe@C nanocapsules were examined by TEM,XRD and a vibrating sample magnetometer.Results show that the Fe@C nanocapsules with diameters in a narrow range of 30-40 nm feature well-constructed core/shell structures,consisting of a bcc-Fe core and a graphitic shell.The Fe@C nanocapsules have a low ratio of remanence to saturation magnetization(M_r/M_s = 0.11),implying that they are superparamagnetic at room temperature.更多还原