金纳米粒子组装体系粒子密度与SERS强度的关系  

Dependence of the Raman Intensity on the Surface Coverage of Nanoparticles in SERS-active Gold Nanoparticulate Films

作　　者：朱梓华[1] 朱涛[1] 王健[1] 刘忠范[1] 

机构地区：[1]北京大学化学与分子工程学院纳米科学与技术研究中心,北京100871

出　　处：《物理化学学报》2000年第2期138-144,共7页Acta Physico-Chimica Sinica

基　　金：国家自然科学基金!(编号29803002)

摘　　要：利用纳米粒子组装技术制备出金基底/巯基苯胺自组装膜偶联层/金纳米粒子的“三明治”结构.实验结果显示 ,该结构对偶联层分子的喇曼光谱显示出很好的增强效应 ,增强因子可达105 ;在表面粒子密度(粒子覆盖度)较低时 ,表面增强喇曼散射(SERS)强度与表面粒子密度近似呈线性关系 ,随着表面粒子密度的增加 ,这种线性关系出现负偏差并在表面粒子密度较高区域出现一个平台 ;在60 -110nm范围内大粒径金粒子对喇曼光谱的增强效果强于小粒径金粒子.高增强因子出现的原因是体系中存在化学增强效应以及纳米粒子与金基底之间的电磁偶合作用 ,初步解释了喇曼强度随粒子密度的变化规律.The relationship between the surface coverage of nanoparticles and the intensity of surface enhanced Raman scattering(SERS) in a two dimensional gold nanoparticulate film was studied. High enhancement was observed due to the nanoparticle substrate electromagnetic coupling and the contribution of chemical enhancement. It was found that SERS intensity increased linearly at lower coverage, then negatively deflected from the initial line, and finally reached a plateau at increased coverages. It was also found that larger nanoparticles were more effective in Raman enhancement.

关 键 词：金纳米粒子 组装 SERS 喇曼光谱 粒子密度 

分 类 号：O647.1[理学—物理化学]