Theoretical and experimental investigation of the flexible Ag nano-tree@Cu mesh SERS substrate

Flexible surface-enhanced Raman spectroscopy (SERS) substrates enable fast sampling and real-time detection, offering greater potential for practical applications. However, whether the flexible substrate will adversely affect the SERS effect when it is bent has rarely been examined in previous studies. In this study, we have tentatively confirmed through theoretical simulations using Ag nano-trees as a model that the effect of bending detection on the SERS effects is negligible. Then, Ag nano-trees were deposited on the surface of a flexible Cu mesh (AgNTs@Cu mesh) by a facile electrochemical method for SERS applications. Successful detection of ultra-low concentrations of rhodamine 6G (R6G, 10−11 M) and crystal violet (CV, 10−10 M) demonstrated the excellent sensitivity of the flexible AgNTs@Cu mesh SERS substrate. In addition, using MG as the target molecule, the SERS signals at different curvature positions on the shrimp surface were detected. In agreement with the theoretical results, the bending did not affect the SERS effect of the substrate. Furthermore, it was experimentally confirmed that the flexible AgNTs@Cu mesh had outstanding in-situ detection capabilities for both solids with uneven surfaces and liquid substances. Therefore, we believe that this work has the potential to provide a universally applicable SERS substrate.