摘要
通过湿化学方法合成了纳米α-Fe颗粒。合成铁纳米颗粒的化学溶液由稀释的二价铁溶液、甲醇和十二烷基硫酸钠组成。在溶液中以NaBH_4为还原剂,将二价铁离子直接还原为α-Fe颗粒,得到的金属铁颗粒以氧化硅进行包覆,在金属铁表面生成致密的氧化硅膜,防止金属铁被再氧化。在铁的合成过程中通入了超声波,以加速药剂的扩散并防止和减小生成物的团聚。以X射线衍射、差热-热重分析和透射电镜对合成产物进行分析和检测。结果表明,采用湿化学法可以直接还原制备α-Fe,其颗粒大小为10~40nm。
The synthesis of α-Fe nanoparticles is carried out by the wet chemical method. The chemical solution consists of diluted Fe62+ solution, methanol,and lauryi sodium sulfate, Fe^2+ is directly reduced with NaBH4 as reductant in the solution, and α-Fe nanaoparticles are obtained. The α-Fe nanoparticles are coated with SiO2, which can prevent the Fe from being oxidized. The synthesis process is controlled by ultrasonic, which can make chemicals diffuse rapidly and avoid aggelomeration. The core-shell nanoparticles are characterized by X ray diffraction(XRD), thermogravimetric/differential thermal analysis (TG/DTA) and transmission electron microscopy (TEM). Results show that the α-Fe nanoparticles are indeed synthesized and the particle size is 10-40 nm.