Wang Zhenming, Liu Jianxun, Wang Jiawei, Ma Zongjun, Kong Delai, Jiang Shouzhen, Luo Dan, Liu Yan Jun
Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China.
Provincial Key Laboratory of Optics and Photonic Device, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China.
Nanomaterials (Basel). 2022 Apr 3;12(7):1202. doi: 10.3390/nano12071202.
Surface-enhanced Raman spectroscopy (SERS) has long been an ultrasensitive technique for trace molecule detection. However, the development of a sensitive, stable, and reproducible SERS substrate is still a challenge for practical applications. Here, we demonstrate a cost-effective, centimeter-sized, and highly reproducible SERS substrate using the nanosphere lithography technique. It consists of a hexagonally packed Ag metasurface on a SiO/Au/Si substrate. A seconds-lasting etching process of a self-assembled nanosphere mask manipulates the geometry of the deposited Ag metasurface on the SiO/Au/Si substrate, which attains the wavelength matching between the optical absorbance of the Ag/SiO/Au/Si substrate and the excitation laser wavelength as well as the enhancement of Raman signals. By spin-coating a thin layer of graphene oxide on the substrate, a SERS performance with 1.1 × 10 analytical enhancement factor and a limit of detection of 10 M for melamine is achieved. Experimental results reveal that our proposed strategy could provide a promising platform for SERS-based rapid trace detection in food safety control and environmental monitoring.
表面增强拉曼光谱（SERS）长期以来一直是用于痕量分子检测的超灵敏技术。然而，开发一种灵敏、稳定且可重复的SERS基底对于实际应用而言仍是一项挑战。在此，我们展示了一种使用纳米球光刻技术制备的具有成本效益、厘米尺寸且高度可重复的SERS基底。它由SiO/Au/Si衬底上的六边形紧密排列的银超表面组成。通过对自组装纳米球掩膜进行持续数秒的蚀刻工艺，可操控SiO/Au/Si衬底上沉积的银超表面的几何结构，从而实现Ag/SiO/Au/Si衬底的光吸收与激发激光波长之间的波长匹配以及拉曼信号的增强。通过在该基底上旋涂一层氧化石墨烯，实现了对三聚氰胺的SERS性能，其分析增强因子为1.1×10，检测限为10 M。实验结果表明，我们提出的策略可为食品安全控制和环境监测中基于SERS的快速痕量检测提供一个有前景的平台。
