VOC photoionization via tuneable monochromatic VUV

We demonstrate photoionization of Volatile Organic Compounds (VOCs) utilizing tuneable quasi-monochromatic Vacuum UltraViolet (VUV) light generated by Third-Harmonic Generation (THG) in suspended SiO2 nanomembranes. We detail efficient THG based on the optimization of nanomembrane thickness and engineering considerations to integrate an effective collection and detection of pico-ampere level photoionization currents. Finally, we establish the sensitivity and selectivity of our setup towards the detection of ethanolamine, limonene and eucalyptol. Our results form a first step towards selective real-time air quality monitoring of problematic toxic high molecular weight VOCs such as benzene, toluene, ethylbenzene and xylene isomers, also known as BTEX compounds.