纳米Zn_(0.6)Co_xFe_(2.4-x)O_4晶粒的结构相变与磁性研究  

Structure phase transition and magnetic properties of nanocrystalline Zn_(0.6)Co_xFe_2.4-x)O_4

作　　者：汪金芝[1] 方庆清[1] 

机构地区：[1]安徽大学物理系,合肥230039

出　　处：《物理学报》2004年第9期3186-3190,共5页Acta Physica Sinica

基　　金：安徽省科学技术带头人项目 (批准号 :0 10 80 2 10 )资助的课题~~

摘　　要：采用溶胶 凝胶自燃烧法制备了纳米尺度的锌钴铁氧体Zn0 6 CoxFe2 4 -xO4 (x =0— 0 30 )粉体 ,分别在不同温度下进行了热处理 ,利用x射线衍射仪 (XRD)和振动样品磁强计 (VSM)对其物相结构和磁性进行了测量和分析 .实验结果表明 ,锌钴铁氧体Zn0 6 Co0 1 5Fe2 2 5O4 在 5 5 0— 80 0℃温度区间出现α Fe2 O3过渡相 ,在高于 80 0℃温度时生成单一尖晶石相锌钴铁氧体 ;随钴含量的增加 ,Zn0 6 CoxFe2 4 -xO4 的比饱和磁化强度先增后减 ,x =0 0 75— 0 1 5比饱和磁化强度较高 ;Zn0 6 CoxFe2 4 -xO4 在 1 30 0℃时x =0 0 75的矫顽力为 4 75 2 0A m ,x≥ 0 1 5时矫顽力在 1 2 0 0℃附近随温度缓慢上升 ,在 1 2 0 0— 1 30 0℃之间为平台状态 ,并且随钴含量的增加 ,矫顽力略有升高 .在x =0 1 0附近 。A series of nanocrystalline powders Zn 0 6 Co x Fe 2 4- x O 4 ( x =0—0 30) was synthesized by the sol gel technique. The structure and magnetic properties was investigated and analyzed through the x ray diffraction (XRD) patterns and the vibrating sample magnetometer (VSM). The experimental results show that α Fe 2O 3 transitional phase appears in the temperature range from 550℃ to 800℃. Single-phase zinc-cobalt ferrites with a spinel structure are obtained when the temperature is beyond 800℃. With relatively higher values of the cobalt content x =0 075—0 15, the specific saturation magnetization climbs up at first and then falls down with the increase of the cobalt content. The coercive force strength H c of Zn 0 6 Co x Fe 2 4- x O 4 reaches its highest value 47520A/m when x =0 075 at 1300℃. H c increases slowly with temperature near 1200℃ when x ≥0 15 and remains in a flat state at 1200—1300℃ and moderate increase is obtained by increasing the x value. High specific saturation magnetization and coercive force can be obtained simultaneously when the cobalt content is near 0 10

关 键 词：锌钴铁氧体 磁光记录材料 溶胶-凝胶法 结构相变 磁化强度 

分 类 号：O484[理学—固体物理]