Ultrasensitive and reusable SERS platform based on Ag modified WO3 nanoflakes for catechol detection

Surface-enhanced Raman spectroscopy (SERS) using the noble-metal/semiconductor hybrid nanostructures are attractive for the real-world detection of organic pollutants due to the unique fingerprint information for analytes and the ultrasensitive detection ability by electromagnetic and chemical mechanisms. In this work, we constructed noble-metal/semiconductor nanostructures by the in-situ deposition of silver nanoparticles (Ag NPs) on tungsten trioxide nanoflakes (WO3 NFs) for the SERS applications. By virtue of the synergistic action of Ag NPs and WO3 NFs, the Ag-NP@WO3-NF nanostructures possess the superior SERS performance, such as ultra-low limit of detection (2.09 x 10-10 M), large analytical enhancement factor (3.90 x 108), high uniformity (less than 8.95%), and good reproducibility (5.20%), for the determination of phenolic derivative, catechol (CT). By its trace-level detection ability, the Ag-NP@WO3-NF nanostructure is employed to detect CT in tap water and the obtained results show satisfactory recovery values with high sensitivity. Moreover, the self-reviving ability of AgNP@WO3-NF nanostructure is demonstrated by the photocatalytic degradation of CT. The experimental results show that the Ag-NP@WO3-NF nanostructure has good detection ability of CT in the five-cycle reusability test. This work paves the way to explore the predominant advantages of noble-metal/semiconductor nanostructure with ultrasensitive and reusable properties for food safety monitoring in real-world applications.