Exhaust gas selective sensing using printed RF gas sensors – CARDIF_Ukraine

Exposure to toxic gases or volatile organic compounds (VOCs) affects safety and public health. More than 6.5 million deaths per year worldwide are attributed to environmental pollution (indoor and outdoor air quality). With the Internet of Things, large-scale deployment of gas sensors becomes accessible to monitor and analyze the environment of individuals, in public or private spaces. This market, driven in particular by the construction, medical industry or consumer applications markets, requires low-energy, low-cost monitoring devices. Portable sensors alone represent a market estimated at 3 billion units in 2025, of which more than 30% are emerging communicating sensors, including chemical sensors, growing exponentially over the next 10 years. In these new markets, research and development of innovative tools is becoming an exciting new field for electronics.
In this context, we propose to address some of the issues related to monitoring the quality of polluted air related to exhaust gases due, for instance, to transports and industrial activity. This has led to specifications in particular for certain harmful vapors such as nitrogen dioxide (NO2), sulfur dioxide (SO2) and ozone (O3) as highlighted in the French regulations. The objective of CARDIF is to respond in particular to the challenge of selectivity, identified as a bottleneck limiting the contribution of conventional metrology in observing or diagnostic systems in a heterogeneous medium. This will be done using functionalized polymers with specific groups.
The current innovative sensors generally suffer from high consumption and / or bulky instrumentation due to low frequency operation, and are mainly based on expensive solutions. As part of the CARDIF project, we propose another type of sensors based on microwave transducers operating at ambient temperature. In addition to being a passive device and therefore not consuming power, they could also operate wirelessly. They are thus suitable for networking and high-frequency communications, usable for real-time detection and providing directly exploitable information. In addition, because of its planar structure, the device can be manufactured on a flexible substrate by low-cost printing technologies.
This multidisciplinary study is made possible thanks to the close collaboration between two industrial (ISORG, Efficacity) and three academic partners (LCPO, IMS, XLIM). Partners have the experience to meet these scientific and technical challenges. To our knowledge, no internationally referenced work has focused on such printed RF gas sensors with optimized selectivity, meeting the following key features:
1 - real-time monitoring of the quality of the outside air,
2 - high sensitivity at room temperature and therefore low energy consumption,
3 - the selective detection of NO2, SO2 and O3 at levels of a few ppb to ppm using functionalized polymers,
4 - low cost manufacturing processes based on collective printing technologies,
5 - new autonomous and wireless solutions, operating in real time thanks to the passive microwave transduction,
6 - outdoor tests following a realistic deployment scenario.
By this way, CARDIF clearly responds to the priorities of the call, in particular the development of sensors for environmental monitoring (smart monitoring)