Fundamentals and applications of recyclable SERS substrates

Surface enhanced Raman scattering (SERS) substrates, composed of plasmonic nanostructures (PNSs) and photocatalyst semiconductors, have emerged as novel multifunctional nanomaterials for advanced engineering applications. These combinations improve the photocatalytic activity of such systems and extend their application as recyclable SERS substrates owing to their self-cleaning ability by photodegradation of analyte molecules. Such combinations allow the fabrication of highly sensitive, reproducible, stable and recyclable SERS substrates. The present article focusses on new developments in design and engineering of such recyclable SERS substrates. The recyclable SERS substrates made of PNSs (Au or Ag NSs) and semiconductor photocatalyst (metal oxides; TiO2, ZnO, WO3, Fe3O4, and others; CdS, conducting polymers, Si NSs) NSs are mainly discussed along with fundamental mechanisms of their multifunctional actions. These recyclable SERS substrates are potential candidates for the detection and elimination of organic compounds (pollutants) as discussed in detail with special emphasis on their reproducibility and long term stability. In addition, current challenges and future potential requirements are also discussed.