DTAB溶液中纳米银的制备

Preparation of Silver Nanoparticles in DTAB Solution

常温磁力搅拌下,在十二烷基三甲基溴化铵(DTAB)体系中用水合肼还原硝酸银制备了颗粒细小均匀的纳米银粉。采用X射线衍射(XRD)、扫描电子显微镜(SEM)和紫外-可见光谱(UV-vis)对产品进行了分析表征。结果表明,纳米银并非是由水合肼直接还原Ag+生成,而是生成的溴化银逐渐被还原后的产物。随着反应时间的变化,体系中首先形成粒度均匀的类球形溴化银,随后转变为多面体的溴化银,最后转变为颗粒细小的纳米银。

Silver nanoparticles with uniform diameters were obtained in dodecyl trimethyl ammonium bromide（DTAB） solution at room temperature under magnetic stirring through hydrazine reducing AgNO3.The products were characterized by XRD,SEM and UV-vis absorption spectra.Results show that the silver nanoparticles are not from the direction reduction of Ag＋ by hydrazine,but the products of the reduced silver bromide which are generated early.As the reaction time increasing,silver bromide of uniform sphere-like structure is gradually converted into nano-polyhedron silver bromide,and into silver nanoparticles finally.