Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, School of Chemical and Environmental Engineering, Jianghan University, Wuhan, 430056, China.
Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, School of Chemical and Environmental Engineering, Jianghan University, Wuhan, 430056, China.
Spectrochim Acta A Mol Biomol Spectrosc. 2020 Mar 5;228:117733. doi: 10.1016/j.saa.2019.117733. Epub 2019 Nov 2.
Silver nanowires (i.e., AgNWs) can act as effective surface-enhanced Raman spectroscopy (i.e., SERS) substrates to detect small molecules. However, a lot of prepared AgNWs were often wrapped by polyvinylpyrrolidone (i.e., PVP) thin film to form an insulating layer to produce ill-defined AgNWs-PVP-AgNWs interface, limiting the plasmonic coupling among the stacked AgNWs. Herein, we reported a facile method in removal of PVP ligands from AgNWs for high performance and reusable SERS substrate. Sodium borohydride (NaBH) was used to completely remove the PVP ligands from the surface of AgNWs and produce a clean AgNWs-AgNWs interface that effectively enhances the localized surface plasmon resonance (i.e., LSPR) was produced, greatly improving the SERS activity of the AgNWs thin film. The SERS detection of rhodamine 6G (i.e., R6G) used with PVP AgNWs and without PVP AgNWs is 1.0 × 10 and 1.0 × 10 M, and the average enhancement factor (EF) is about 0.86 × 10 and 9.35 × 10, respectively. Moreover, the recyclable behavior of the AgNWs with several analyte molecules is much more interesting than that of the PVP@AgNWs. The SERS detection of AgNWs for R6G, the 3-mercaptopropionic acid (i.e., 3-MPA) and melamine with good recyclability in nanomolar and millimolar concentration can be easily detected.
银纳米线(即 AgNWs)可用作有效的表面增强拉曼光谱(即 SERS)基底,以检测小分子。然而,大量制备的 AgNWs 通常被聚维酮(即 PVP)薄膜包裹,形成绝缘层,产生不明确的 AgNWs-PVP-AgNWs 界面,限制了堆叠 AgNWs 之间的等离子体耦合。在此,我们报道了一种从 AgNWs 上去除 PVP 配体的简便方法,以获得高性能和可重复使用的 SERS 基底。使用硼氢化钠(NaBH)完全去除 AgNWs 表面的 PVP 配体,并产生干净的 AgNWs-AgNWs 界面,有效地增强了局域表面等离子体共振(即 LSPR),极大地提高了 AgNWs 薄膜的 SERS 活性。用 PVP AgNWs 和无 PVP AgNWs 检测的罗丹明 6G(即 R6G)的 SERS 检测浓度分别为 1.0×10 和 1.0×10 M,平均增强因子(EF)分别约为 0.86×10 和 9.35×10。此外,与 PVP@AgNWs 相比,具有多个分析物分子的 AgNWs 的可回收行为更有趣。AgNWs 对 R6G、3-巯基丙酸(即 3-MPA)和三聚氰胺的 SERS 检测具有良好的纳米摩尔和毫摩尔浓度的可回收性,可轻松检测。