Facile synthesis of two‐dimensional PA‐Ag@C film for highly sensitive SERS detection

In this study, the surface of polyamide (PA) films are electrostatically deposited with the carbon‐coated silver (Ag@C) nanoparticles, resulting in a two‐dimensional (2D) PA‐Ag@C film substrate. The TEM images demonstrate that the nanoparticles were successful synthesized. By adjusting the pH of the system, the core–shell structure and the 2D SERS substrate work together to improve the sensitivity, stability, and repeatability of the substrate to be used in complex real‐world water samples. The SERS enhancement effect and substrate uniformity were determined using rhodamine 6G (R6G), crystal violet (CV), and malachite green (MG). The results indicate that the 2D PA‐Ag@C film substrate in this study has the optimal Raman effect at a system pH of 6. Under ideal pH conditions, the R6G detection limit (LOD) is as low as 10 −10 M (D2 attenuation), and the Raman signal intensity deviation of the same substrate is maintained within 9.49%. Overall, the Raman signal of probe molecule on the fabricated PA‐Ag@C film possesses excellent sensitivity, repeatability, and stability.