不同粒度纳米银的可控合成

Controlled synthesis of silver nanoparticles with different particle sizes

由于纳米银的许多特殊性能均取决于其粒度,因此制备粒度可控且均一的球形纳米银是非常重要的。以硝酸银为银源,鞣酸和柠檬酸钠为还原剂,制备了不同粒度的球形纳米银颗粒。实验分别考察了硝酸银、鞣酸和柠檬酸钠的用量,以及混合温度对粒度的影响,并分析了影响机理。通过X射线衍射仪和场发射扫描电子显微镜对所制备的不同粒度球形纳米银的结构和形貌进行了表征。结果表明,采用双还原剂液相还原法能够制备分散度好、粒度均一的球形纳米银。随着硝酸银用量的增加,纳米银的粒度变化不大,且呈现先增加后减小的趋势。随着鞣酸用量的增加,柠檬酸钠用量的减小和混合温度的升高,纳米银的粒度逐渐增加。

It is very important to prepare spherical silver nanoparticles with controllable and uniform particle size because many special properties of silver nanoparticles depend on their particle size.Spherical nano-Ag with different diameters was prepared by using AgNO as silver source,tannic acid and sodium citrate as reducing agents.The effects of the amounts of silver nitrate,tannic acid and sodium citrate,and the mixed temperature on the particle size were studied,and the effect mechanism was explored.The structure and morphology of the spherical nano-Ag with different diameters were characterized by X-ray diffractometer and field emission scanning electron microscopy.The results show that the spherical nano-Ag with good dispersion and uniform particle size can be prepared by liquid phase reduction method with double reductant.With the increase of the amount of silver nitrate,the diameter of nano-Ag has no great change,first it increases and then decreases slightly.With the increase of tannic acid dosage,the decrease of sodium citrate dosage and the increase of mixed temperature,the diameter of nano-Ag increased gradually.