文献类型：期刊文献

英文题名：Multifunctional Fe3O4@Ag/SiO2/Au Core-Shell Microspheres as a Novel SERS-Activity Label via Long-Range Plasmon Coupling

作者：Shen, Jianhua[1];Zhu, Yihua[1];Yang, Xiaoling[1];Zong, Jie[1];Li, Chunzhong[1]

机构：[1]E China Univ Sci & Technol, Sch Mat Sci & Engn, Minist Educ, Key Lab Ultrafine Mat, Shanghai 200237, Peoples R China

年份：2013

卷号：29

期号：2

起止页码：690

外文期刊名：LANGMUIR

收录：;EI(收录号：20130415939295);WOS:【SCI-EXPANDED(收录号:WOS:000313667300021)】；

基金：We thank the National Natural Science Foundation of China (20925621, 20976054, and 21176083), the Special Projects for Nanotechnology of Shanghai (11 nm0500800), the Fundamental Research Funds for the Central Universities (WD1013015 and WD1114005), the Program for Changjiang Scholars and Innovative Research Team in University (IRT0825), and the Shanghai Leading Academic Discipline Project (project number: 13502) for financial supports.

语种：英文

外文关键词：Biocompatibility - Plasmons - Shells (structures) - Solutions - Surface scattering - Magnetite - Raman scattering - Molecules - Nanostructures

摘要：Noble metallic nanostructures exhibit a phenomenon known as surface-enhanced Raman scattering (SERS) in which the Raman scattering cross sections are dramatically enhanced for the molecules adsorbed thereon. Due to their wide accessible potential range in aqueous solutions and the high biocompatibility, Au supports are preferred for spectro-electrochemical investigations. However, the optical range in SERS spectroscopy is restricted to excitation lines above 600 nm, which is shorter than the Ag supports. In addition, these SERS-activity materials are not easy to separate and reused. Herein, the present article reports the novel multifunctional Fe3O4@Ag/SiO2/Au core-shell microspheres that display long-range plasmon transfer of Ag to Au leading to enhanced Raman scattering. The well-designed microspheres have high magnetization and uniform sphere size. As a result, Fe3O4@Ag/SiO2/Au microspheres have the best enhancement effect in the Raman active research by using Rhodamine-b (RdB) as a probe molecule. The enhancement factor is estimated to be 2.2 x 10(4) for RdB from the long-range plasmon transfer of Ag to Au, corresponding to an attenuation of the enhancement by a factor of only 0.672 x 10(4) compared to RdB adsorbed directly on the Fe3O4@Ag microspheres. RdB can be detected down to 10(-9) M even without the resonance SERS effect. The unique nanostructure makes the microspheres novel stable and a high-enhancement effect for Raman detection.