Real-time, High Precision Greenhouse Gas Measurements Using A Mid-Infrared Laser-Based Platform

H.J. Jost, James J. Scherer, Joshua B. Paul and Jacob Thekkethala, Thermo Fisher Scientific

Real-time, ultra sensitive measurement is required for a wide array of applications, including pollution and GHG monitoring. Traditional approaches such as non-dispersed infrared absorption (NDIR) and Chemiluminescence are slowly being augmented or in some cases replaced with new, laser-based analyzers that are capable of providing realtime ppb-level detection of key atmospheric species. Monitoring of chemical species via their associated fundamental ovibrational bands in the mid-infrared is well established. The requisite selectivity and sensitivity for monitoring greenhouse gases, industrial pollutants, and combustion precursors, intermediates, and products have been demonstrated in numerous studies. Utilizing technology acquired from NovaWave Technologies, we are now developing a new difference frequency generation (DFG) based, mid-infrared laser analyzer platform that is capable of monitoring numerous species with high sensitivity and selectivity. Specifically, the O-H, N-H, and C-H stretch region between 3-4 microns and the C-O and N-O stretch region between 4-4.6 microns is being used to monitor the three primary greenhouse gases; CH₄ CO₂, and N₂O.