Ag@SiO_2的制备及其SERS活性研究  

Preparation of Ag@SiO_2 Nanoparticles and Its SERS Study

作　　者：李向敏[1,2] 胡智萍[1,2] 张振龙[1,2] 高惠平[1,2] 毛艳丽[1,2] 

机构地区：[1]河南大学物理与电子学院,开封475004 [2]河南大学计算材料科学研究所,开封475004

出　　处：《光散射学报》2015年第2期139-143,共5页The Journal of Light Scattering

基　　金：国家自然科学基金(21103043);河南省科技发展计划项目(142102210389)

摘　　要：本文用柠檬酸三钠还原硝酸银的方法制得银纳米粒子,并且通过调节加入正硅酸乙酯(TEOS)的量形成不同包裹厚度的Ag@SiO2。用紫外可见吸收光谱、扫描和透射电子显微镜测试手段对样品进行了分析和表征。获得了比较均匀的银纳米颗粒,加入TEOS后,在银纳米颗粒的周围包裹了一层二氧化硅膜,形成分散性较好的Ag@SiO2纳米颗粒。通过吡啶分子来探测不同SiO2厚度的Ag@SiO2的包裹致密性以及增强效果,选出增强效果最好的Ag@SiO2作为SERS基底,并把它运用于检测农药的残留问题。实验结果表明当加入1!L的TEOS时形成的Ag@SiO2纳米颗粒包裹得均匀致密并且拉曼增强效果很好。The different coating thickness of Ag@SiO2 are obtained by adding tetraethoxysi- lane （TEOS） to package a lay of SiO2 on the surface of Ag nanoparicles,where the Ag nanop- articles are synthesized by aqueous reduction of AgNO3 with trisodium citrate. Surface mor- phology and optical properties of Ag@SiO2 are studied using UV-Vis spectroscopy,TEM and SEM,respectively. Experimental results indicate that Ag nanoparticles are uniform and coa- ted by SiO2 film,and the obtained Ag@SiO2 nanoparticles have good dispersion. Using pyridine as probe molecule,Raman spectra of pyridine adsorbed on Ag@SiO2 are taken to test the compactness and SERS activity. The Ag@SiO2 nanoparticles with the best Raman enhance- ment effect are applied to detect a residue of pesticides. Experimental results show that the Ag@ SiO2 nanoparticles are uniform and compact, while the Raman enhancement effect is strongest when the adding amount of TEOS is 1μL.

关 键 词：Ag@SiO2纳米颗粒 表面增强拉曼光谱 吡啶 丙溴辛硫磷 

分 类 号：O648.124[理学—物理化学]