粒径可控纳米银的制备研究

Study on the Preparation of Controlled Sizes of Silver Nanoparticles

以次磷酸钠液相还原法制备纳米银溶胶。通过调节还原后银溶胶的pH值可以达到控制纳米银粒径的效果。研究了氨水在制备不同粒径的银粉过程中的作用。对银溶胶进行了Zeta电位测量。对制得的纳米银样品用XRD、TEM进行了表征。采用原子吸收法分析了还原后溶液中残留的银离子的浓度，确定银的还原率。分析了各种因素对纳米银制备和样品粒径的影响。通过控制适当合成反应条件，可制得10-100nm、粒径可控、高分散性、高纯度的纳米银粉。

A silver colloid is prepared through reaction of silver nitrate solution with sodium hypophosphite. The sizes of silver nanoparticles are controlled by adding ammonia solution in order to changing pH of the silver sol. The morphology and structure of synthesized silver nanoparticles are characterized by transmission electron microscopy （TEM）and X-ray diffraction （XRD）. Experiment shown that the metal silver nanoparticles, with controlled sizes and high decentralization can be prepared by using this simple method.