以LiOH-H2O,Fe2O3和草酸为原料,通过流变相反应,制得草酸盐结构的Li铁氧体前驱体。将前驱体在远低于通常的固相反应的温度下进行热处理,得到Li铁氧体纳米粒子。这一反应通过LiFeO2作为中间相来完成。用XRD和VSM对制得的Li铁氧体粉体进行了表征。结果表明,所得铁氧体为纳米粒子,具有有序结构,且具有较高的饱和磁化强度和矫顽力。纳米晶Li铁氧体粉料表现出良好的微波吸收特性。
The precursor of Li ferrite with an oxalate composition was prepared via a rheological phase reaction of LiOH.H2O, Fe2O3 and oxalic acid. Nanocrystalline Li ferrite powders were obtained after heat treatment of the precursor under a temperature much lower than required in conventional solid state reaction. LiFeO2 was the intermediate of the formation of Li ferdte. The ferrites were characterized by an XRD and VSM method. The results showed that the ferdtes were nanocrystalline particles with ordered structure of Li+ and Fe^3+ ions in the octahedral sited of the ferrite. The magnetization of the ferrite nanoparticles was higher than that of the samples synthesized by sol-gel method and the corcivity of the ferrite was higher than that of the bulk ferrite. The well absorbing performance in the microwave range was obtained for the nanocrystalline Li-ferrite powders.