Surface enhanced Raman scattering in the near infrared using metal nanoshell substrates
Surface enhanced Raman scattering in the near infrared using metal nanoshell substrates
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DOI：
10.1063/1.479235
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发表时间：
1999-09-08
影响因子：
4.4
通讯作者：
Halas, NJ
中科院分区：
文献类型：
--
作者：
Oldenburg, SJ;Westcott, SL;Halas, NJ
金属纳米壳是由薄金属壳包覆的介电核组成的复合纳米颗粒;其峰值等离子体共振波长由核直径与壳厚度的比率决定。当p-巯基苯胺（p-MA）与金纳米壳（在1.06 μ m激发源附近具有等离子体共振）溶液中时，观察到显著的表面增强拉曼散射（Sers）。当足够的金沉积在二氧化硅核上以形成几乎完整的金属壳时，获得最强的拉曼增强。透射电子显微镜（TEM）定义的结构，紫外（UV）-可见光谱，Sers信号强度和电磁理论之间的相关性表明，Sers信号是由于通过纳米结构的等离子体共振的介电场的局部增强和由几乎完成的金壳提供的局部区域的高场强。与完整纳米壳结构上的Sers增强的比较表明了这两种效应的相对贡献。(C)1999年美国物理学会。[S0021-9606（99）70733-6]。
A metal nanoshell is a composite nanoparticle consisting of a dielectric core coated by a thin metal shell; its peak plasmon resonance wavelength is determined by the ratio of the core diameter to the shell thickness. When p-mercaptoaniline (p-MA) is in solution with gold nanoshells that have their plasmon resonance near a 1.06 mu m excitation source, significant surface enhanced Raman scattering (SERS) is observed. The strongest Raman enhancements are obtained when enough gold is deposited on the silica cores to form a nearly complete metal shell. Correlations between transmission electron microscopy (TEM)-defined structure, ultraviolet (UV)-visible spectra, SERS signal strength, and electromagnetic theory show that the SERS signal is due to both the local enhancement of the dielectric field via the plasmon resonance of the nanostructure and to the localized regions of high field intensity provided by the nearly completed gold shell. Comparison with SERS enhancements on completed nanoshell structures indicates the relative contribution of these two effects. (C) 1999 American Institute of Physics. [S0021-9606(99)70733-6].