微波辐照纳米银的制备与表征

Preparation and characterization of nano-silver particles via microwave irradiation

在微波辐照下,以硝酸银为银源,水为溶剂,聚乙烯吡咯烷酮（PVP）为稳定剂和还原剂,不加入其他还原剂的条件下,快速制备出纳米银胶体。利用紫外光谱法,对微波制备纳米银粒子的条件进行了一系列研究,得出了先40℃下预热15min,再微波辐照30min,微波功率为260W,AgNO3∶PVP=1∶3（质量比）为最佳制备条件。对制得的纳米银粒子进行了TEM、SPM、DTA表征,发现制得的纳米银粒子为球形粒子,粒径较小,且粒径分布较窄,为18-25nm。对PVP的作用机理研究认为：主要是由于Ag离子与PVP的配位作用和PVP的空间位阻效应,使得能够制备出纳米球形银粒子。

Black nano silver sols were rapidly synthesized from AgNO3 aqueous solution containing PVP via microwave irradiation under the best experiment condition which was gained from a series of factor experiments by ultraviolet visible（UV-vis） spectrophotometer.The best synthesis condition was that the mass ratio of AgNO3 and PVP was 1∶3,AgNO3 solutions were preheated for 15 minutes at 40℃,then via microwave irradiation for 30 minutes with microwave power of 260 W.And nano-silver particles were characterized by TEM,SPM,DTA.The results showed that prepared nano-silver particles had narrow particle size distribution,single spherical shape and the average size was about 18~25nm.Then we found that the role of PVP in the spherical nano-silver＇s preparation was that the coordination bond could be formed between Ag＋ and PVP,and PVP had special steric effect.