Ag纳米粒子生长动力学的局域表面等离子体共振研究  

Growth Kinetics of Ag Nanoparticles Studied by Localized Surface Plasmon Resonance

作　　者：陈丽华[1,2] 徐刚[1] 徐雪青[1] 王春平[3] 

机构地区：[1]中国科学院广州能源研究所可再生能源与天然气水合物重点实验室,广东广州510640 [2]中国科学院研究生院,北京100080 [3]四川大学物理科学与技术学院,四川成都610000

出　　处：《高校化学工程学报》2009年第2期284-289,共6页Journal of Chemical Engineering of Chinese Universities

基　　金：国家自然科学基金资助项目(50876108);国家863计划(2007AA05Z431);粤港关键领域重点突破项目(200649851105)资助

摘　　要：采用Meisel方法利用氧化还原反应制备Ag纳米粒子溶胶,通过对Ag纳米粒子局域表面等离子体共振(SPR)吸收光谱的实时观测,研究了Ag纳米粒子形成的动力学过程,并着重探讨了温度对Ag纳米粒子生长过程的影响。实验发现,SPR吸收峰的移动与实验条件有密切关系。采用恒温磁力搅拌直接加热的方式,Ag纳米粒子的SPR吸收峰在整个反应过程中主要体现为红移,其反应动力学主要表现为零级反应,反应速率与温度符合Arrhenius关系,并粗略估算了一定反应条件下的反应活化能;而采用恒温磁力搅拌水浴加热方式,SPR吸收峰则呈现红移→蓝移→红移交替移动现象。初步探讨了SPR吸收峰的红、蓝移影响因素及其移动机理,得出SPR峰的移动方向是粒径大小与电荷转移相互竞争的结果。Colloidal sols of Ag nanoparticles were fabricated with Meisel＇s method via redox reactions. The growth kinetics of the Ag nanoparticles in some conditions was investigated in real time by the absorbance spectrum of localized surface plasmon resonance （SPR） of nano-Ag in which the influence of solution temperature was stressed. It reveals that the shift of the SPR peak with reaction time is strongly dependent on the experimental conditions. In case of direct heating method, the SPR peak shows merely red-shift. The reaction order was determined to be zero, the dependence of reaction rate on temperature follows the Arrhenius＇ Law; and activation energy of reaction was calculated. In contrast, in case of water-bath heating method, red-shift alternats with blue-shift of the SPR peak in the initial stage of redox reaction, whereas only red-shift appears in the final stage. Such observations were tentatively attributed to the competition between the growth of Ag nanoparticle size which leads to red-shift and electron transfer which results in a change in free electron concentration of Ag and may cause red-shift or blue-shift of the SPR peak.

关 键 词：AG纳米粒子 表面等离子体共振 吸收光谱:生长动力学 

分 类 号：O433.51[机械工程—光学工程] O614.122[理学—光学]