线球状银颗粒的液相合成及其机理研究

Fluffy Silver Microspheres: Synthesis by Chemical Solution Route and Formation Mechanism

本文在三嵌段共聚物PluronicF127/十二烷基硫酸钠(SDS)混合表面活性剂体系中制备了直径为3～4μm的线球状Ag颗粒。实验发现随着体系中SDS浓度的增加,组成Ag微球的亚单元从椭球状经由棒状变成了纳米线。动态光散射数据表明随着SDS的加入,F127胶束被F127/SDS混合胶束所取代,且混合胶束尺寸随着SDS浓度的变化而变化。实验表明SDS的烷基链段与F127的憎水PPO链段的相互吸引作用,以及SDS亲水基团之间的静电排斥作用将影响产物的最终结构。

Loosely aggregated silver microspheres have been synthesized by the redox reaction between silver nitrate （AgNO3） and ascorbic acid （C6H8O6） in the presence of sodium dodecyl sulfate （SDS） and the triblock copolymer Pluronic F127 （EO97PO68EO97）. The subunits of silver microspheres change from ellipsoids, through rods, and ultimately to threads with an increase in the concentration of SDS. Dynamic light scattering investigation shows that the addition of SDS induces the break down of F127 micelles and results in the formation of F127/SDS mixed micelles. The attractive hydrophobic interaction between the alkyl group of SDS and PPO block of F127 may play an important role in the fabrication of silver microspheres by subunits with different morphologies.