Department of Chemistry, ‡Department of Physics and Astronomy, §Department of Electrical and Computer Engineering, and ⊥Laboratory for Nanophotonics, Rice University , 6100 Main Street, Houston, Texas 77005, United States.
Nano Lett. 2015 Feb 11;15(2):1272-80. doi: 10.1021/nl504455s. Epub 2015 Jan 12.
Here, we report a new nanoantenna for surface-enhanced infrared absorption (SEIRA) detection, consisting of a fan-shaped Au structure positioned at a well-specified distance above a reflective plane with an intervening silica spacer layer. We examine how to optimize both the antenna dimensions and the spacer layer for optimal SEIRA enhancement of the C-H stretching mode. This tunable 3D geometry yields a theoretical SEIRA enhancement factor of 10(5), corresponding to the experimental detection of 20-200 zeptomoles of octadecanethiol, using a standard commercial FTIR spectrometer. Experimental studies illustrate the sensitivity of the observed SEIRA signal to the gap dimensions. The optimized antenna structure exhibits an order of magnitude greater SEIRA sensitivity than previous record-setting designs.
在这里，我们报告了一种新的纳米天线，用于表面增强红外吸收（SEIRA）检测，该天线由一个扇形 Au 结构组成，位于具有间隔二氧化硅层的反射平面上方的特定距离处。我们研究了如何优化天线尺寸和间隔层以实现 C-H 伸缩模式的最佳 SEIRA 增强。这种可调谐的 3D 几何形状产生了 10(5)的理论 SEIRA 增强因子，使用标准商业 FTIR 光谱仪可检测到 20-200 飞摩尔十八烷硫醇。实验研究说明了观察到的 SEIRA 信号对间隙尺寸的敏感性。优化后的天线结构表现出比以前的记录保持设计高一个数量级的 SEIRA 灵敏度。
