Extinction Spectra of 1,4-Benzenedimethanethiol on Gold Nano Pillars with varying dimensions

Through direct write electron beam lithography, periodic patterns with well-defined nano-roughness were fabricated reproducibly with varying pillar distance and size. Upon functionalization with 1, 4-benzenedimethanethiol, the optical reflectivity spectra of the surface were measured in the visible and near infrared at normal incidence using a custom built optical arrangement on Olympus BX 51 microscope (Photonics Lab UNSW School of Physics). In this set-up, a USB2000+ miniature fibre optic spectrometer (Ocean Optics Inc., USA), having a spectral resolution of 1 nm, was coupled to a multimode fibre with the collecting facet mounted in the conjugate image plane of the microscope. The microscope was equipped with a 20x objective. The collecting aperture of the fibre-coupled spectrometer had a diameter of 100 μm. Reflectivity spectra were recorded and processed using the SpectraSuite spectroscopy software platform (Ocean Optics Inc., USA).Below are information about the gold nano pillarsNo. Size/nm2 Distance/nm 1 (100) (100)2 (100) (300)3 (300) (100)4 (300) (300)5 (59) (200)6 (341) (200)7 (200) (59)8 (200) (341)9 (200) (200)10 (200) (200)

通过直写电子束光刻（direct write electron beam lithography）技术，可重复制备出具有规整纳米粗糙度的周期性图案，且柱体间距与尺寸均可灵活调控。采用1,4-苯二甲硫醇（1, 4-benzenedimethanethiol）对该表面完成功能化修饰后，借助定制搭建的光学实验装置，在奥林巴斯BX 51显微镜（Olympus BX 51 microscope）上以正入射方式测量了可见光及近红外波段的表面反射光谱。该实验装置中，光谱分辨率为1 nm的USB2000+微型光纤光谱仪（USB2000+ miniature fibre optic spectrometer，Ocean Optics Inc., 美国）通过多模光纤连接，其收集端面安装于显微镜的共轭像平面内。显微镜配备20倍物镜，光纤耦合式光谱仪的收集孔径直径为100 μm。反射光谱的采集与处理通过SpectraSuite光谱软件平台（SpectraSuite spectroscopy software platform，Ocean Optics Inc., 美国）完成。以下为金纳米柱的相关参数：
| 编号 | 尺寸（nm²） | 间距（nm） |
|------|------------|-----------|
| 1 | (100) | (100) |
| 2 | (100) | (300) |
| 3 | (300) | (100) |
| 4 | (300) | (300) |
| 5 | (59) | (200) |
| 6 | (341) | (200) |
| 7 | (200) | (59) |
| 8 | (200) | (341) |
| 9 | (200) | (200) |
| 10 | (200) | (200) |