Au/MIL-101 (Fe) Nanocomposite Substrate: A Synergistic SERS Platform Combining Electromagnetic and Chemical Enhancement

Electromagnetic enhancement in SERS is achieved through the surface plasmon resonance (SPR) effect of gold nanoparticles. When gold nanoparticles are excited by an external light source, the free electrons on their surface undergo resonance oscillation driven by an electric field. This generates surface plasmon waves, which can focus and enhance the incident light field. As a result, the Raman scattering signal of molecules or ions attached to the surface of gold nanoparticles is greatly enhanced.\nChemical enhancement in SERS is achieved through the interfacial reaction between gold nanoparticles and MIL-101 (Fe). MIL-101 (Fe) is a Metal–organic framework that possesses a highly ordered pore structure and a large specific surface area. When gold nanoparticles interact with MIL-101 (Fe), the electronic states on the surface of the gold nanoparticles couple with the local electric field of MIL-101 (Fe). This leads to charge transfer and polarization effects at the interface. These effects enhance the interaction between molecules or ions and gold nanoparticles, further amplifying the SERS signal.\nBy combining both electromagnetic and chemical enhancement, the Au/MIL-101 (Fe) nanocomposite substrate achieves a synergistic SERS effect. This results in improved sensitivity and detectability of SERS signals, making it a promising platform for various applications in sensing, imaging, and detection.