液相化学还原法制备的超细钴粒子

Magnetic ultrafine cobalt particles prepared by solution chemical reduction method

以水合肼为还原剂、以酒石酸钾钠为络合剂,利用液相还原法在无醇水溶液中还原钴离子而制备钴粒子。X射线衍射(XRD)分析表明纳米钴粒子具有hcp结构。用透射电镜(TEM)和振动样品磁强计(VSM)对钴粒子进行表征,结果显示粒子为球状纳米钴粒子,平均粒径随反应温度的升高和CoSO4.7H2O与主络合剂酒石酸钾钠浓度比的增大及反应液pH值的增大而增大,钴粒子的比饱和磁化强度随反应液pH值的升高而升高。该制备方法具有工艺简单、还原反应过程易于控制、钴粒子粒径可调范围大等优点。

Coblat particles have been prepared by solution chemical reduction method in non-alcohol solution, using hydrazine hydrate as reducing agent and potassium sodium tartrate as complexing agent. X-ray diffraction （XRD） analysis indicateed that the Co particles prepared have close-packed hexagonal structure（hcp）. Transmission electron microscope（TEM） and vibrating sample magnetometer（VSM） analysis indicated that the nanosized subround Co particles were prepared. The average particle diameter increases with increasing the temperature, concentration ratio of COSO4＂7H20 to seignette sol and the pH value. The specific saturation magnetization increases as the pH value increasing. The advantage of this method is that the press is simple and reduction reaction is easy to be controlled, and the Co particles can be changed in a wide range of mean particle size.