Sub-Second, Sensitive and Multispecies Detection of Volatile Organic Compounds Using a Mid-Infrared Broadband Supercontinuum Source and Upconversion Spectrometer.

Reliable monitoring and analysis of volatile organic compounds (VOCs) are crucial for environmental monitoring and human health. In this work, we report a system for fast, sensitive, and multispecies detection of VOCs by combining a fiber-based broadband mid-infrared (MIR) supercontinuum (SC) source with an upconversion spectrometer. The system's performance in terms of species identification accuracy, robustness against inter-species interference and real-time multi-species detection capability was evaluated by monitoring and tracing the evaporation dynamics of three VOCs, i.e., acetone, ethanol, and α-pinene. We achieved detection limits of 30 parts per million per meter (ppm·m), 5 ppm·m, and 0.6 ppm·ּּm in 1 second for these three compounds, respectively. Furthermore, the evaporation behavior of individual compounds from a mixture was investigated to demonstrate the system's capability for dynamic multicomponent analysis.