金纳米粒子的绿色可控合成及其合成机理研究

Green controlled synthesis of gold nanoparticles and its reaction mechanism

以水溶性淀粉为还原剂,以氯金酸为前驱体,快速合成了单分散的金纳米粒子。采用紫外-可见吸收光谱(UV-Vis)、透射电子显微镜(TEM)、X射线衍射(XRD)、能谱仪(EDX)等对金纳米粒子进行表征。结果表明,合成了面心立方结构的球状金纳米粒子,其平均直径不大于40nm,表面等离子体共振吸收峰在534~552nm之间线性可调。系统考察了水溶性淀粉的水解时间、氯金酸添加量、反应时间等制备条件对金纳米粒子光学性能的影响并对金纳米粒子的合成机理进行了研究。实验发现,最佳水解时间为5min,增加反应时间或氯金酸的添加量,金纳米粒子的吸收峰均发生规律性红移。

The monodisperse Au nanoparticles （NPs） were rapidly synthesized with the soluble starch andchloroauric acid as the reduce agent and the precursor of Au element, respectively. Au NPs were characterizedusing the ultraviolet-visible spectrophotometer （UV-Vis） , transmission electron microscope （TEM） , X-ray dif-fraction （XRD） and energy dispersive X-Ray spectroscopy （EDX）. It was found that spherical Au NPs withface-centered cubic phase and the average diameter size less than 40nm were synthesized and their surfaceplasma resonance （SPR） peak was lineally controlled in the range from 534 to 552 nm. Effects of the hydrolysistime, the adding quantity of chloroauric acid and the reaction time on optical properties of Au NPs were investi-gated. The optimal hydrolysis time was 5 min. The SPR peak of Au NPs was regularly red-shifted with theincrease of the reaction time and the adding quantity of chloroauric acid.