To make surface enhanced Raman scattering (SERS) sensors more practical, we propose nanoporous Ag disks as SERS-active plasmonic structures that can be readily inkjet-printed just before use to avoid degradation of SERS enhancement. Together with the aid of the enhanced plasmonic fields from the nanoporous Ag (confirmed by electromagnetic simulation), we utilize a coffee-ring effect to concentrate target analytes, which is demonstrated by confocal Raman measurements. By using the proposed SERS sensor, Raman signals of TiO₂ nanoparticles with a concentration of ppm to sub-ppb have been successfully measured. TiO₂ in commercial consumables has been also detected by distinguishing its crystalline phase.

为了使表面增强拉曼散射（SERS）传感器更加实用，我们提出了纳米多孔Ag盘作为SERS活性等离激元结构，可以在使用前方便地进行喷墨打印，以避免SERS增强的劣化。借助纳米多孔银的增强等离子体场（通过电磁仿真确认），我们利用咖啡环效应来浓缩目标分析物，这通过共聚焦拉曼测量得到了证明。通过使用提出的SERS传感器，已成功测量了浓度为ppm至亚ppb的TiO ₂纳米颗粒的拉曼信号。商用消耗品中的TiO ₂也通过区分其晶相而被检测到。