Au-coated ZnO nanorods on stainless steel fiber for self-cleaning solid phase microextraction-surface enhanced Raman spectroscopy

• Au-coated ZnO nanorods on stainless steel fiber as a SERS-active SPME fiber was fabricated.
• The SERS-active SPME fiber can directly extract and detect the crystal violet and malachite green.
• The SERS-active SPME fiber owns good extraction effect, and high SERS sensitivity.
• Self-cleaning property of the fiber were achieved based on the photocatalytic degradation property of ZnO.

Solid phase microextraction-surface enhanced Raman spectroscopy (SPME–SERS), combining the pretreatment and determination functions, has been successfully used in environmental analysis. In this work, Au-coated ZnO nanorods were fabricated on stainless steel fiber as a self-cleaning SERS-active SPME fiber. The ZnO nanorods grown on stainless steel fiber were prepared via a simple hydrothermal approach. Then the obtained nanostructures were decorated with Au nanoparticles through ion-sputtering at room temperature. The obtained SERS-active SPME fiber is a reproducible sensitivity sensor. Taking p-aminothiophenol as the probe molecule, the RSD value of the SERS-active SPME fiber was 8.9%, indicating the fiber owned good uniformity. The qualitative and quantitative detection of crystal violet and malachite green was also achieved. The log–log plot of SERS intensity to crystal violet and malachite green concentration showed a good linear relationship. Meanwhile, this SERS-active SPME fiber can achieve self-cleaning owning to the excellent photocatalytic performance of ZnO nanorods. Crystal violet was still successfully detected even after five cycles, which indicated the high reproducibility of this SERS-active SPME fiber.

Au-coated ZnO NRs on stainless steel fiber were used as SERS-active SPME fiber with good extraction effect, high SERS sensitivity. Self-cleaning function of the fiber was achieved based on the photocatalytic degradation property of ZnO nanorods by UV irradiation.Figure optionsDownload as PowerPoint slide