纳米Zn0.6CoxFe2.4－xO4晶粒的结构相变与磁性研究

采用溶胶 凝胶自燃烧法制备了纳米尺度的锌钴铁氧体Zn06CoxFe24-  xO4(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Zn06Co015Fe 225O4在550—800℃温度区间出现α Fe2O3过渡相，在高于800℃温度时生 成 单一尖晶石相锌钴铁氧体；随钴含量的增加，Zn06CoxFe2 关键词： 锌钴铁氧体 磁性 结构 相变 溶胶 凝胶

Structure phase transition and magnetic properties of nanocrystalline Zn0.6CoxFe2.4-xO4

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 mag netic properties was investiga ted and analyzed through the x ray diffraction (XRD) patterns and the vibrating sample magnetometer (VSM). The experimental results show that α Fe2O3 tra nsitio nal 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 d o wn 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 increas es slowly with temperature near 1200℃ when x≥015 and remains in a flat s tate at 1200—1300℃ and moderate increase is obtained by increasing the x value. High specific saturation magnetization and coercive force can be obtained simultaneo usly when the cobalt content is near 010