Au纳米颗粒的制备及光限幅效应研究

Research on the Preparation and Optical Limiting Effect of Au Nanoparticles

分别采用两相法和水相法制备颗粒大小不同的Au纳米颗粒,通过紫外-可见吸收光谱和电子透射显微镜研究了表面保护剂剂量与粒径大小关系,发现表面保护剂增加会使Au纳米颗粒粒径降低,且分级纯化法会降低粒径分布范围。在此基础上对不同方法制备的Au纳米颗粒进行非线性光限幅测试。两相法制备的Au纳米颗粒的光限幅阈值比水相法制备的Au纳米颗粒低,但随着入射能量的增大,水相法制备的Au纳米颗粒的光限幅效果优于两相法Au纳米颗粒。

Two kinds of Au NPs with different sizes were respectively prepared by aqueous-phase method and two-phase method. The dosage of surface protective agent was negatively related to the size of Au nanoparticles,which was found by using Uv-vis absorption spectra and TEM. In addition,Stepwise purification method could reduce the distribution range of the particle size. Moreover,nonlinear optical limiting test showed that the Au NPs prepared by two-phase method have a lower optical limiting threshold than that of Au NPs prepared by aqueous-phase method. But for the Au NPs prepared by two-phase method,the output energy flow density raises with the increase of incident energy,which indicates that optical limiting effect of Au NPs in aqueous phase is better at high energy level.