溶胶pH值对CoFe_2O_4/SiO_2复合薄膜结构和磁性能的影响  

Effect of pH value for sol on the structure and magnetic properties of CoFe_2O_4/SiO_2 nanocomposite thin films

作　　者：刘宇[1] 李季[1] 华杰[1] 沈维霞[1] 李海波[1] 

机构地区：[1]吉林师范大学凝聚态物理与材料科学研究所,吉林四平136000

出　　处：《电子元件与材料》2010年第12期8-10,共3页Electronic Components And Materials

基　　金：吉林省科技发展计划资助项目(No.20090517)

摘　　要：采用sol-gel法制备了纳米CoFe2O4/SiO2复合薄膜(样品)。利用X射线衍射仪、原子力显微镜、振动样品磁强计对样品的结构、形貌和磁性能进行了研究。结果表明:随着溶胶pH值的减小,样品中CoFe2O4的平均晶粒尺寸变小,CoFe2O4晶粒沿(111)晶面择优取向生长。样品的矫顽力随着平均晶粒尺寸的减小明显变大,当溶胶pH值为0.29时,垂直和平行膜面的矫顽力分别为290 kA.m–1和250 kA.m–1,样品具有较明显的垂直磁各向异性。当溶胶pH值为0.59时,样品垂直和平行膜面的剩磁比(Mr/Ms)分别为53.2%和51.5%。CoFe2O4/SiO2 nanocomposite thin films were prepared by the sol-gel method.The structure,morphology and magnetic properties of prepared thin films were investigated using X-ray diffraction（XRD）,atomic force microscope（AFM） and vibrating sample magnetometer（VSM）.The results show that the average grain size of CoFe2O4 in the sample decreases with decreasing pH value of sol,and the CoFe2O4 grain has a obvious preferred orientation in（111）.The coercivity of the sample increases with the decrease of the average grain size.The sample possesses perpendicular magnetic anisotropy with out-of-plane coercivity（Hc⊥） of 290 kA·m^–1 and in-plane coercivity（Hc∥） of 250 kA·m^–1 when the pH value of sol is 0.29.The remanence ratios（Mr/Ms） in both the directions of the sample with pH = 0.59 of sol are 53.2% and 51.5%,respectively.

关 键 词：SOL-GEL法 CoFe2O4/SiO2 纳米复合薄膜 结构 磁性能 

分 类 号：O482.5[理学—固体物理]