Nitrous oxide (N2O) and carbon monoxide (CO) are important drivers in global warming. However, there are many difficulties in reliable monitoring, especially for N2O, as the concentration of N2O in atmospheric is only a few hundred parts per billion. However, the compatibility precision recommended by World Meteorological Organization (WMO)is much lower. Therefore, a solution that can offer more precise monitoring is needed.
Recently, a research team led by Professor GAO Xiaoming of Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science (HFIPS) developed a dual gas sensor with high precision and low drift to measure atmospheric N2O and CO. Related findings were published in Sensors and Actuators B: Chemical
In this research, researchers designed an improved White Cell to obtain long optical path length (76 m) at a short base length (34.5 cm). The radio frequency noise was equipped to low optical fringes. Combined with an Interband Cascade Laser (ICL), they got a high precision spectrometer for atmospheric greenhouse gases N2O and CO.
With this spectrometer, researchers can test micro-daily-drift (less than 1.5 part per trillion). The precisions of N2O and CO reached 0.065 part per billion and 0.133 part per billion, respectively, which successfully met the requirement of WMO.
This work provides a potentially valuable laser spectrometer for highly precise measurement of greenhouse gases, which is of great significance to the monitoring and suppression of global warming.
Source: http://english.hf.cas.cn/