稀土Dy^(3+)掺杂Fe_3O_4纳米颗粒的合成与磁性

Synthesis and Superparamagnetism of Dy^(3+)-doped Fe_3O_4 Nano-particles

以二价、三价硫酸铁和硝酸镝、氢氧化钠为原料,合成出Dy掺杂铁氧体纳米颗粒,并用月桂酸进行了表面修饰。用透射电镜(TEM)、X射线衍射仪(XRD)对颗粒的形貌、晶型结构进行了表征,用振动样品磁强计(VSM)测量其磁性能。XRD测试结果表明产物的结构为面心立方尖晶石型;TEM照片表明产物的成球性好,且大部分颗粒的粒径在13~15nm左右;室温下的磁化曲线表明产物无剩磁和矫顽力,具有超顺磁性。并且发现,与相同工艺、相同条件下合成的未掺杂Fe3O4纳米颗粒相比,Dy掺杂铁氧体纳米颗粒的磁性能显著提高。

Dy-doped Fe3O4 ferrite nano-particles were synthesized using ferrous sulfate,ferric sulfate,dysprosium nitrate,and sodium hydroxide as raw materials,and the surface was modified by lauric acid.The morphology,crystal structure of the magnetic particles were characterized by transmission electron microscopy(TEM) and X-ray diffraction(XRD).The magnetic properties were measured by vibration sample magnetometer(VSM).XRD results showed that the particles have a structure of fcc spinel type;TEM photographs showed that the particle size is about 13-15nm;room temperature magnetization curves showed that the particles are superparamagnetic,without remanent magnetization and coercivity.Compared to pure Fe3O4 nanoparticles prepared under the same conditions,Dy-doped Fe3O4 nanoparticles have an enhanced magnetization.