Air pollution is one of the major environmental issues that humanity is facing. Considering Indoor Air Quality (IAQ), Volatile Organic Compounds (VOCs) are among the most harmful gases that need to be detected, but also need to be eliminated using air purification technologies. In this work, we tackle both problems simultaneously by introducing an experimental setup enabling continuous measurement of the VOCs by online absorption spectroscopy using a MEMS-based Fourier Transform infrared (FTIR) spectrometer, while those VOCs are continuously eliminated by continuous adsorption and photocatalysis, using zinc oxide nanowires (ZnO-NWs). The proposed setup enabled a preliminary study of the mechanisms involved in the purification process of acetone and toluene, taken as two different VOCs, also typical of those that can be found in tobacco smoke. Our experiments revealed very different behaviors for those two gases. An elimination ratio of 63% in 3 h was achieved for toluene, while it was only 14% for acetone under same conditions. Adsorption to the nanowires appears as the dominant mechanism for the acetone, while photocatalysis is dominant in case of the toluene. Introduction The development of human industrial activities, daily life habits and increasing urbanization are leading to an intensification of environmental pollution, mainly of water and air by chemical agents. These include volatile organic compounds (VOCs) such as aldehydes, ketones, hydrocarbons, aromatics. .. and semi-volatiles such as polycyclic aromatic hydrocarbons (PAHs); inorganic compounds such as CO, Nox, O 3 and heavy metals. VOCs are harmful to public health and contribute into climatic changes [1,2]. The issue of air quality becomes an important topic and increases the research to find solutions to the purification of the air we breathe and also water. The aim is to develop innovative, low-cost, selective, environmentally friendly materials capable of capturing and destroying these pollutants, in conjunction with a real time monitoring technology. Such real time monitoring is crucial as it will enable triggering the operation of depollution systems when needed, hence improving their