Recyclable NiO/g-C3N4/ag hybrid substrates for sensitive SERS detection and photo-degradation of residual pesticides in beverages

In this research, we fabricated an innovative NiO/CN/Ag composite through the straightforward electrostatic assembly of Ag nanoparticles and g-C 3 N 4 sheets onto NiO nanoflowers. This composite enables both surface enhanced Raman spectroscopy (SERS) detection and photo-degradation of pesticides. The results reveal NiO/CN/Ag can quantitatively detect thiram (TRM) and diquat dibromide (DQDB) in water, with a limit of detection (LOD) of 10 −9  M, and also exhibit outstanding photo-degradation efficiency, exceeding 95 % for TRM and DQDB within 90 min under simulated sunlight. Significantly, after the organic reagent (citric acid) on NiO/CN/Ag was completely removed through simulated solar irradiation, the signal-to-noise ratios of SERS spectra on NiO/CN/Ag were enhanced, achieving LODs of 10 −8  M for TRM and DQDB in different fruit juices and dried flower teas. Additionally, the composite demonstrate impressive recyclability, maintaining robust SERS signals and high degradation rates even after five cycles of “detection-degradation” processes.