核壳结构Ni@SiO_2纳米粒子的可控合成及磁性能研究  

Controllable synthesis and magnetic property of core-shell structure Ni@SiO_2 nanoparticles

作　　者：鲜华[1] 周宏[1] 郎雷鸣[1] 

机构地区：[1]南京晓庄学院生物化工与环境工程学院,南京211171

出　　处：《华中师范大学学报（自然科学版）》2010年第4期605-609,共5页Journal of Central China Normal University：Natural Sciences

基　　金：江苏省科技厅高校自然科学研究指导性项目(10KJD150009)

摘　　要：采用了简单的液相还原方法,以硼氢化钠为还原剂,聚乙烯吡咯烷酮(PVP-K30)作为高分子表面活性剂,成功合成了分散性较好、尺寸比较均一的镍纳米粒子.通过改变氯化镍以及PVP的用量,获得多种尺寸和形貌的镍纳米颗粒.以分散性较好的镍纳米粒子为包裹对象,碱催化正硅酸乙酯水解缩合,制备了形貌可控的Ni@Si O2核壳结构纳米粒子,并系统研究了乙醇与水的比例、正硅酸已酯的用量以及反应速度对其形貌的影响。运用XRD、TEM、SEM、EDS等技术分别对所合成的产品进行表征,磁性能测试表明该复合纳米粒子在低温下具有很大的矫顽力,为2350 Oe.Well-dispersed Ni nanoparticles were synthesized successfully by the simple reduction method using NaBH4 as reducing agent and PVP as surfactant. The condition experiments showed that Ni nanoparticles with different shapes and sizes could be obtained by changing the amount of nickel chloride or PVP. Coreshell struture Ni@SiO2 nanoparticles were prepared via the hydrolysis condensation of TEOS on the surface of Ni nanoparticles with the help of ammonia. The acting factors of Ni@SiO2 nanoparticles morphologies change were investigated systemically, including the volume ratio of alcohol to water, the concentration of TEOS and reaction rate. Several techniques, such as XRD, TEM, SEM and EDS, were used to characterize the products. Magnetic property indicated that Ni@SiO2 nanoparticles have a high coercivity of 2350 Oe at 1.8 K.

关 键 词：Ni@SiO2 核壳结构 可控合成 磁性能 

分 类 号：O657[理学—分析化学]