Li Honggang, Baum Caitlin E, Sun Jian, Cullum Brian M
Department of Chemistry and Biochemistry, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, Maryland 21250, USA.
Appl Spectrosc. 2006 Dec;60(12):1377-85. doi: 10.1366/000370206779321562.
We have developed a novel class of gold multilayer, surface-enhanced Raman scattering (SERS) substrates that are capable of enhancing SERS signals by 15.3-fold over conventional gold film over nanostructure (GFON) SERS substrates, making them comparable in sensitivity to optimized silver film over nanostructure (SFON) substrates, while providing the long-term stability obtained from gold. They are fabricated by depositing 10 A thick silver oxide islands on conventional GFON substrates, followed by deposition of a second continuous gold layer. The silver oxide layer acts as a dielectric spacer between the two continuous gold films and produces significantly enhanced SERS signals, as compared to optimized single layer substrates of the same geometry or comparable substrates prepared by deposition of silver islands that are not oxidized. In addition to the enhanced sensitivity of these multilayer substrates, they also exhibit long SERS active shelf-lives (i.e., months), with no measurable degradation in SERS enhancement, and relative standard deviations in SERS enhancement of less than 5.2% across the substrate's surface.
我们开发了一种新型的金多层表面增强拉曼散射（SERS）基底，与传统的纳米结构上的金膜（GFON）SERS基底相比，它能够将SERS信号增强15.3倍，使其在灵敏度上与优化后的纳米结构上的银膜（SFON）基底相当，同时还具备金所提供的长期稳定性。它们是通过在传统的GFON基底上沉积10埃厚的氧化银岛，然后再沉积第二层连续的金层来制备的。与相同几何形状的优化单层基底或通过沉积未氧化银岛制备的可比基底相比，氧化银层充当两个连续金膜之间的电介质间隔层，并产生显著增强的SERS信号。除了这些多层基底具有增强的灵敏度外，它们还具有较长的SERS活性保质期（即数月），SERS增强效果没有可测量的降解，并且在整个基底表面上SERS增强的相对标准偏差小于5.2%。
