关键词: 纳米金制备, 柠檬酸钠还原剂, 硼氢化钠还原剂, 聚乙烯吡咯烷酮(PVP), 透射电子显微镜

Abstract: Gold nanoparticles with various diameters were synthesized by chemical reduction. UV-Vis spectroscopy and transmission electron microscopy (TEM) were used to characterize the morphology and the size of the prepared Au nanoparticles. The effects of factors, such as the type of the reducing agent, the amount of the reducing reagent, reagent adding order and reaction temperature on the stability, radius, morphology and dispersion of Au nanoparticles were studied. The results show that the size of Au nanoparticles prepared with Na₃C₆H₅O₇ as a reductant was within the range of 15~20 nm, and the size of Au nanoparticles prepared with NaBH₄ as a reducing agent was within the range of 3~10 nm. The optimum molar ratio of Na₃C₆H₅O₇ and HAuCl4 was 1.5:1. The gold nanoparticles prepared after adding HAuCl₄ to the hot mixture of Na₃C₆H₅O₇ and poly vingl pyrrolidone (PVP) solution were better dispersed, smaller in size and more uniform, compared with that prepared after adding Na₃C₆H₅O₇ to the hot mixture of HAuCl₄ and PVP solution.

Key words: preparation of gold nanoparticles, Na₃C₆H₅O₇ reducing agent, NaBH₄ reducing agent, poly vingl pyrrolidone (PVP), transmission electron microscopy (TEM)