Aramid nanofibers (ANFs) as an innovative nanoscale building block exhibit great potential for novel high-performance multifunctional membranes attributed to their extraordinary performance. However, the application of aramid nanofibers in the field of surface enhanced Raman scattering (SERS) sensing has been rarely reported. In this work, aramid nanofibers derived from commercial Kevlar fibers were synthesized by a facile dimethyl sulfoxide/potassium hydroxide (DMSO/KOH) solution treatment. The monodispersed silver nanoparticle-decorated aramid nanofiber (m-Ag@ANF) membranes were constructed by an efficient vacuum filtration technique. Taking advantages of unique intrinsic properties of ANF, the m-Ag@ANF substrates exhibit good flexibility, excellent mechanical properties and prominent thermal stability. Besides, due to the abundance of positively charged amino-group on the ANF substrates, the negatively charged m-AgNPs were uniformly and firmly deposited on the surface of ANF substrate through electrostatic interactions. As a result, the optimal flexible m-Ag-9@ANF SERS substrate exhibits high sensitivity of 10^-9 M for methylene blue (MB) and excellent signal reproducibility (RSD = 6.37 %), as well as outstanding signal stability (up to 15 days). Besides, the 2D Raman mapping and FDTD simulations further reveal prominent signal homogeneity and strong electric field distribution for flexible m-Ag-9@ANF SERS substrate. Finally, it is demonstrated that the flexible m-Ag-9@ANF SERS substrate can also be used for detection of toxic molecules on irregular surfaces by a feasible paste-and-read process. The m-Ag@ANF paper exhibits potential applications as a flexible, low-cost, robust and stable SERS sensing platform for trace detection of toxic materials.

芳纶纳米纤维（ANF）作为一种创新的纳米级结构单元，因其非凡的性能而展现出新型高性能多功能膜的巨大潜力。然而，芳纶纳米纤维在表面增强拉曼散射（SERS）传感领域的应用却鲜有报道。在这项工作中，通过简单的二甲基亚砜/氢氧化钾（DMSO/KOH）溶液处理合成了源自商业凯夫拉纤维的芳纶纳米纤维。单分散银纳米颗粒装饰的芳纶纳米纤维（m-Ag@ANF）膜是通过高效的真空过滤技术构建的。利用ANF独特的固有特性，m-Ag@ANF基底表现出良好的柔韧性、优异的机械性能和突出的热稳定性。此外，由于ANF基底上存在大量带正电荷的氨基，带负电荷的m-AgNPs通过静电相互作用均匀且牢固地沉积在ANF基底表面。因此，最佳的柔性 m-Ag-9@ANF SERS 基底对亚甲基蓝 (MB) 表现出 10 ^-9 M 的高灵敏度和出色的信号重现性 (RSD = 6.37 %)，以及出色的信号稳定性 (高达15天）。此外，二维拉曼图和FDTD模拟进一步揭示了柔性m-Ag-9@ANF SERS基底突出的信号均匀性和强电场分布。最后，证明灵活的 m-Ag-9@ANF SERS 基板还可以通过可行的粘贴和读取过程用于检测不规则表面上的有毒分子。 m-Ag@ANF 纸展示了作为灵活、低成本、强大且稳定的 SERS 传感平台的潜在应用，用于有毒材料的痕量检测。