A critical review of the analytical performance of the most recent MOS-based gas sensors for indoor air quality monitoring of WHO priority pollutants

In the past few years, there has been significant progress in developing sensors for indoor air quality (IAQ) monitoring. Thanks to their miniaturization, low cost, and growing concerns for people's well-being, these sensors have become increasingly important. This paper reviews the latest metal oxide semiconductor (MOS)-based gas sensors published since 2019 for the WHO-priority gas pollutants. While MOS-based gas sensors initially had limitations, including low selectivity, high operating temperatures leading to high power consumption, and interference from humidity, these challenges have been overcome. Currently, MOS-based sensors can detect some of the WHO-priority target gases at room temperature, achieving guideline values established for human safety. This progress in MOS-based gas sensors instills optimism for their future role in IAQ monitoring despite the challenges that still need to be addressed.