摘要
以次磷酸钠液相还原法制备纳米银胶体，通过加入氨水调节银溶胶pH，使纳米银粒子长大、产生聚沉。控制聚沉过程的工艺条件（pH，氨水浓度、氨水滴加速度、搅拌、超声等），可使纳米银粉从银溶胶中直接过滤出来。通过对银溶胶Zeta电位的测定以及滤液中银离子含量的测定，分析了氨水在固液分离中的作用和纳米银的产率。提供了从银溶胶中过滤纳米银粉的新方法，该法工艺简单、对设备要求低、能耗小、银粉的损失率小，而且易于实现工业化。样品经过TEM和XRD分析发现，该法制备的纳米银粉平均粒径为40nm（pH=4～5），纯度高，分散性好。
Silver nanoparticles were prepared by the reduction of silver nitrate solution with sodium hypophosphite in polyvinylpyrrolidone solution. Coagulation of silver sols was found by adding ammonia solution. Some technical conditions, such as pH, ammonia concentration, ammonia dropping velocity and stirring rate were tested in order to get silver nanoparticles by filtrating silver sols. The results show that the separation of solid silver nanoparticles with liquid solution is improved and silver nanoparticles with different size are produced. Technical conditions of this method are simple and only need some ordinary apparatuses Moreover, the method consumed less energy and got high nanoparticle silver productivity. Therefore, it feasible method for mass production of silver nanoparticles. The products were measured by transmission electron microscope （TEM） and X-ray diffraction （XRD）. It is shown that silver particles are spherical form with diameter about 40 nm at pH = 4 - 5, and the particles are pure metal silver with high dispersibility.
出处
《稀有金属》
EI
CAS
CSCD
北大核心
2006年第2期153-157,共5页
Chinese Journal of Rare Metals
基金
四川省纳米技术专项(03GG009-030)资助
关键词
纳米银粉
银溶胶
固液分离
制备
液相还原法
silver nanoparticles
silver sol
solid-liquid separation
preparation
reduction reaction
