纳米Fe3O4粒子的制备及表面包覆.pdfVIP

第28卷第 6期 青 岛科 技 大 学 学 报(自然科学版) Vo1．28 No．6 2007年 12月 Journal of Qingdao University of Science and Technology(Natural Science Edition) Dec．2007 文章编号：1672—6987(2007)06—0477—04 纳米Fe3 o4粒子的制备及表面包覆 胡迎花 罗志聪。陈克正 (青岛科技大学材料科学与工程学院，山东 青岛266042) 摘 要：采用化学共沉淀法和氧化沉淀法制备磁性纳米Fe。O 粒子，并用柠檬酸三钠为 表面活性剂包覆制备纳米 Fe。O 粒子，同时利用包覆磁性粒子制备水基纳米磁性液体。 对两种方法制备的纳米Fe。O 粒子的晶体结构、微观形貌及化学共沉淀法制备的Fe。O 在包覆前后等电点的变化进行了表征。结果表明，化学共沉淀法制备的纳米Fe。O 粒子 平均粒径约为20 nnl且分布比较均匀，表面活性剂包覆后，等电点由原来的PH一6．70 移向pH一2．35，证实了Fe。O 粒子表面被柠檬酸离子所包覆，且制得的磁性液体的稳定 性比较高；而氧化沉淀法制备Fe。O 纳米粒子粒径分布是从几十纳米到上百纳米，制得 的磁性液体出现很明显的团聚。 关键词：纳米Fe。O 粒子；化学共沉淀法；氧化沉淀法；磁性液体；表面包覆 中图分类号：TM 27 文献标识码：A Preparation and Surfaces Modification of Magnetic Fe3 04 NanOparticIes HU Ying-hua，LUO Zhi-cong，CHEN Ke-zheng (College of Materials Science and Engineering，Qingdao University of Science and Technology，Qingdao 266042，China) Abstract：Magnetic Fe3 O4 nanoparticles were prepared by the chemical CO—precipitation and oxidation precipitation methods，and the water—base magnetic fluids were obtained by dispersing sodium citrate—coated nanoparticles into water．The morphologies and si— zes of the Fe3 04 particles were investigated and the isoelectric points of Fe3 O4 prepared by chemica1 co-precipitation method after modification with／without sodium citrate were determined．The results showed that the average size of Fe3 O4 nanoparticles prepared by chemical CO—precipitation method was about 20 nm，which was much smaller than that of the particles prepared by the oxidation precipitation method．The isoelectric points of Fe3 O4 particles prepared by chemical CO—precipitation method before and after modifica— tion with sodium citrate were at pH一6．70 and pH 一 2．35，respectively