Recyclable three-dimensional Ag nanorod arrays decorated with O-g-C3N4 for highly sensitive SERS sensing of organic pollutants

[Display omitted] •The Ag NRs/O-g-C3N4 substrate was successfully fabricated via a facile process.•The substrate possessed the outstanding Raman enhancement ability to the analytes.•The substrate exhibited long-term stability and high reproducibility.•The substrate can be used for recyclable detection and degradation of organic pollutants. A three-dimensional (3D) substrate was developed by assembling a monolayer of graphitic carbon nitride (O-g-C3N4) on Ag nanorod arrays (Ag NRs) for sensitive and recyclable surface enhanced Raman scattering (SERS) detection. The prepared Ag NRs/O-g-C3N4 substrate not only generated a significant Raman enhancement effect as a result of the strong π-π stacking interaction between O-g-C3N4 and the analytes but also possessed excellent self-cleaning property via visible-light irradiation that was attributed to its outstanding catalytic performance. Highly sensitive SERS detection could be achieved with a LOD of 8.2 × 10−10 M for R6 G, and the substrate could be used repeatedly for at least four cycles with tolerable intensity attenuation. In addition, the 3D substrate exhibited long-term stability originating from the electron-donor effect of O-g-C3N4 and high reproducibility due to the uniform decoration of O-g-C3N4 on the Ag NRs through the strong interaction. Furthermore, using Ag NRs/O-g-C3N4, the recyclable detection of antibiotics in a water sample was demonstrated with high sensitivity, which indicates that the 3D Ag NRs/O-g-C3N4 substrate is a promising candidate for eliminating the challenges of single-use SERS substrates and building a portable SERS platform to sense organic molecular species.