Insight on a novel Raman spectroscopy based analytical sensor in tracing asphalt volatile organic compounds

Asphalt Volatile Organic Compounds (VOCs) pose significant environmental impacts and health risks, and associated detection and quantitative analysis methods are widely concerned in recent decades. The study proposed to develop a novel SERS substrate with flower-like silver nanospheres (AgNPs) and ZIF-8 for the Surface-Enhanced Raman Scattering (SERS) based portable gas Raman detection system, whose morphology and crystal structure are interpreted by X-ray diffraction (XRD) and Scanning electron microscopy (SEM). After verbalizing the prepared substrate, the repeatability and stability of proposed SERS substrate are measured in analyzing asphalt VOCs. The results indicate that optimizing the concentration of AgNPs to 30 μL could uniformly distribute the coat and form numerous hotspots on the substrate to enhance the Raman signal. The SERS substrate demonstrates excellent repeatability and stability, accurately identifying the characteristic pollutants of asphalt VOCs with a relative standard deviation (RSD) less than 10 %. It achieves a high sensitivity, capable of detecting toluene concentrations down to 0.1 ppm and successfully quantified the toluene concentration in asphalt VOCs as 6.871 mg/cm 3 . This advancement makes the SERS technology be a promising tool for effective monitoring of asphalt VOCs emissions, offering significant potential for environmental monitor and pollutants control.