A compact multigas sensor system detecting CO2 and CH4 simultaneously for climate, health, and safety

We develop in-house a multi-gas sensor system by fabricating micro-channels on silicon (Si) chips and demonstrating its ability to detect and monitor both CO2 and CH4 concentration levels simultaneously. Our multi-gas sensor leverages on non-dispersive infrared (NDIR) sensing mechanism that measures the drop in voltage due to the molecular fingerprint absorption at the mid-IR wavelength range by the C=O and C-H bonds at λ ~ 4.3 μm and λ ~ 3.6 μm respectively. CO2 and CH4 are mixed in different concentrations and passed through the multi-gas sensor for sensing response. Our results show that this multi-gas sensor could measure CO2 down to 90 ppm and CH4 down to 240 ppm respectively with response time < 3 s. This compact multi-gas sensor system could be deployed into settings such as in power plants, petrochemical and mining industries to monitor gases in the environment to ensure health and safety of human lives.