Remote Activation of Flexible Magnetoelectric Membrane to Enhance In Situ SERS Response

In situ surface‐enhanced Raman scattering (SERS) enables the monitoring of dynamic processes in chemistry and biology. However, highly sensitive in situ SERS detection remains a challenge in complex environments. In this study, a magnetoelectric composite membrane with SERS properties that can be actively tuned by remotely applied magnetic fields is presented. Owing to the magnetoelectric coupling effect, the applied magnetic field can change the surface potential of the composite membrane, thus modulating the local electric field strength of the silver nanoparticles on the membrane surface. Further enhancement of the SERS signals of rhodamine 6G, crystal violet (CV), malachite green, and 4‐nitrothiophenol is achieved in the presence of a magnetic field. Furthermore, experiments show that the in situ SERS signals of dopamine in aqueous solution, CV on shrimp surfaces, and human‐secreted sweat can be successfully enhanced by applying an external magnetic field. The remote SERS enhancement technique proposed in this study provides an innovative approach for highly sensitive in situ detection in complex environments.