摘要
以Ba(NO3)2和Fe(NO3)3为原料与不同比例的柠檬酸在水溶液中形成溶胶,把溶胶滴于脱脂棉模板上,水分挥发后在脱脂棉表面形成凝胶,于马弗炉中850℃煅烧2h后制得了BaFe12O19微管,并在最佳柠檬酸用量时对BaFe12O19微管进行掺杂制得了BaLaxFe12-xO19(x=0～0.3)微管。利用X射线衍射(XRD)﹑扫描电子显微镜(SEM)﹑透射电子显微镜(TEM)对样品的物相﹑形貌和粒径进行表征,并利用振荡样品磁强计(VSM)对样品进行磁性能研究。结果表明:借助脱脂棉模板,采用溶胶凝胶法制备了外径在8～13μm之间,壁厚在0.5～2μm之间的BaFe12O19微管,柠檬酸的加入使得微管出现破裂,随着柠檬酸用量的增加,BaFe12O19微管的矫顽力和饱和磁化强度先提高后下降,随着La掺入量的增加BaFe12O19微管的矫顽力、饱和磁化强度以及剩余磁化强度都先增加后减小,但饱和磁化强度和剩余磁化强度的最大值滞后于矫顽力的最大值,当柠檬酸与金属离子的物质的量之比为1∶1,x为0.05时850℃煅烧后制得了矫顽力、饱和磁化强度和剩余磁化强度分别为6153.6Oe,61.1和36.1emu.g-1的BaLaxFe12-xO19微管。并就柠檬酸和La掺杂对微管的形成和磁性能的影响原理做了系统的研究。
BaFe12O19, citric acid and Ba（NO3）2 were used as crude material to form sol in the solvent. The sol formed gel on the surface of the absorbent cotton template. The Barium ferrite microtubules were prepared after the calcinations process. The BaFe12O19（x =0-0.3） microtubules were obtained by this method. The phase, morphology, particle diameter, and the magnetic property of samples were detected by XRD, SEM, TEM and VSM. It was found that the external diameter of BaFe12O19 microtubules were between 8 μm and 13 μm, the wall thickness were between 0.5 μm and 2μm. The adding of citric acid led to the fragmentation of the microtubules. As the increase of the content of citric acid and La, the coercive force, the residual magnetization and the saturation magnetization of the samples increased, and then decreased. But the maximum of the saturation magnetization lag behind the maximum of the residual magnetization. When the molar ratio of citric acid to the metal ion was 1：1, and the calcinations temperature was 850℃, the coercive force, the saturation magnetization and residual magnetization of the samples were 6 153.6Oe, 61.1 and 36.1 emu.g^-1 respectively. The formation of microtubules and its effect on the magnetic property were studied.
出处
《无机化学学报》
SCIE
CAS
CSCD
北大核心
2009年第2期312-316,共5页
Chinese Journal of Inorganic Chemistry
基金
国家自然科学基金资助项目(No.20571066
20871108)
