纳米Co粒子的制备及在硅油基磁性液体中的应用
来源期刊：中南大学学报(自然科学版)2006年第4期
论文作者：张茂润 周红梅 李广学
文章页码：720 - 725
关键词：纳米Co粒子;硅油基复合磁性液体;饱和磁化强度
Key words：nano-Co particles; silicon-oil based ferrum magnetic liquid; saturation magnetization
摘 要：以锌粉和氯化钴为原料,采用化学法制备纳米Co粒子。采用透射电镜考察工艺条件对生成的Co粒子粒径及晶貌的影响。通过对不同粒径Co粒子的筛选,确定了用于制备磁性液体的适宜粒径。纳米Co经表面活性剂改性后与适量的纳米Fe3O4胶粒混合,用过渡液进行复合包覆,使用超声波振荡和机械分散的方法将其分散于2-甲基硅油中,得到硅油基复合磁性液体。用振动样品磁强计测定样品的饱和磁化强度。研究结果表明:在反应物浓度一定的条件下, Co粒子的晶貌主要由反应温度决定;对Co粒子粒径影响最大的是反应温度,其次是搅拌转速,反应时间对Co粒子粒径的影响不大。Co粒子用作磁性液体基体材料的适宜粒径约为10.88 nm,晶貌主要为六面体和棒形。复合磁性液体的饱和磁化强度比Fe3O4磁性液体的饱和磁化强度提高21%以上。
Abstract: The nano-Co particles were prepared by chemical method from zinc dust and cobalt chloride. The influence of technological conditions on Co particle size and its crystal morphology was observed by transmission electron microscopy. By screen separating Co particles with different diameters, the particles with proper diameter were chosen to prepare magnetic liquid. The nano-Co particles were mixed with nano-Fe3O4 colloidal particle after the surfactant s property was improved, then they were coated with transition liquid and dispersed in 2-methyl silicon-oil in the way of ultrasonic oscillating and mechanical dispersing. In this way, silicon-oil based ferrum magnetic liquid was prepared. The saturation magnetization of the liquid was measured by vibrating sample magnetometer. The results show that the particle s morphology is mainly determined by reaction temperature when the density of reactant remains the same; the diameter of Co particle is determined by reaction temperature and the mixing speed, whereas reaction time poses almost no influence. The diameter of the particles suitable for the matrix materials of magnetic liquid is about 10.88 nm, whose shapes are mainly hexahedron and clavatus. Compared with that of magnetic Fe3O4 liquid, the magnetization saturation of the ferrum magnetic liquid is increased bymore than 21%.
