金银合金纳米粒子的制备

Synthesis of Au-Ag Alloy Nanoparticles

以柠檬酸钠为稳定剂,利用硼氢化钠还原AgNO3和HAuCl4混合溶液制备了Au-Ag合金纳米粒子,UV-Vis光谱谱图只观察到一个位于纯银和纯金之间的表面等离子体共振峰,且该表面等离子体共振峰的最大吸收波长与合金中Au的摩尔分数成线性关系.TEM结果表明:Au-Ag合金纳米粒子的粒径大约为43 nm,且颜色均一,没有明显的核壳结构.

Gold-silver alloy nanoparticles were prepared in a solution made by reducing HAuCh and AgNO3 with sodium borohydride and using trisodium citrate as a capping agent. Only a surface plasmon resonance peak was observed in the UV-Vis spectra and the SPR band of Au-Ag nanoparticles shifts linearly to the red with increasing Au content. Due to TEM, nanoparticles are about 43 nm and lack an apparent core-shell structure. It is concluded that the nanoparticles are alloys rather than core-shell composites.