桑叶提取液快速绿色合成单分散银纳米粒子

Rapid and Green synthesis of monodisperse silver nanoparticles using mulberry leaf extract

摘要:

报道了一种在水溶液中的简单、快速、绿色制备5到15nm纳米银溶胶的方法。在这种方法中，硝酸银为银源，桑叶提取液为还原剂和保护剂，没有利用其它的还原剂和保护剂，在常温下制备纳米银。纳米溶胶的颜色从浅黄色变到棕色，表明生成了纳米银粒子。利用紫外可见光谱（UV-vis），透射型电子显微镜（TEM），红外光谱（FT-IR）和X-射线衍射（XRD）对样品进行了分析。结果表明所得到的银粒子为分散性较好、粒径较小、结晶度很高、被植物提取液包覆的球状纳米银颗粒。通过UV光谱对反应温度、反应时间、银离子浓度及提取液用量对粒径的影响进行了研究，提出了一种可能的反应机理。该方法可以扩展到用其它可再生的物质来制备贵金属纳米粒子。

Abstract:

A simple, rapid and eco-friendly technique for the preparation of small-size silver nanoparticles with narrow distribution from 5 nm to 15 nm was developed. In the approach, using silver nitrate as silver precursor, and mulberry leaves extract as both capping and reducing agent, silver nanoparticles were obtained at room temperature, without employing any other reducing and capping agents. The formation of silver nanoparticles was observed by the change of color from pale yellow to brown and the UV-vis absorption spectroscopy. The effect of reaction time, temperature, silver nitrate concentration and mulberry leaves extract amount were studied. The silver nanoparticles were characterized by transmission electron microscopy (TEM), UV-visible spectroscopy (UV-vis), X-ray diffraction (XRD) and fourier-transform infrared spectroscopy (FT-IR). The results demonstrated that the obtained metallic nanoparticles were highly crystalline silver nanoparticles with a spherical shape and capped with extract. A possible formation mechanism was proposed. The method demonstrated in this paper may be extended to synthesize other noble metal nanoparticles by using renewable materials as capping and reducing agents.