Ultra-Accurate Dual-Gas Sensor Tracks Greenhouse Gasses Down to 65 Parts Per Trillion
Designed for research into climate change this high-precision gas sensor is good to 133 parts per trillion CO and 65 parts per trillion N₂O.
A team of scientists from the Hefei Institutes of Physical Science and the University of Science and Technology of China have unveiled a new dual-gas sensor, which offers a major boost in nitrous oxide and carbon monoxide monitoring precision over the competition.
Developed by a research team led by Gao Xiaoming, professor at Heifi Institutes' Anhui Institute of Optics and Fine Mechanics, the laser spectrometer sensor aims to solve a key problem in monitoring environmental nitrous oxide and carbon monoxide as drivers of climate change: The fact they can be found in concentrations as low as a few hundred parts per billion.
The newly-developed sensor is based around a 4.54μm room temperature interband cascade laser, tuned to cover the absorption lines of both N₂O and CO simultaneously, along with an improved White cell sensor designed to reduce optical interference noise. Coupled with a technique for handling long-term drift, the sensor's performance proved impressive.
"By further precisely [controlling] the temperature and pressure of the absorption cell, a continuous 24h measurement precision of 65 ppt [parts per trillion] N₂O and 133 ppt CO at 0.1Hz was demonstrated, with a daily drift less than 1.5 ppt," the team reports in its paper. "Finally, the repeatability and reliability of the sensor system were validated by real atmospheric measurements for two consecutive days."
The sensor, which is designed to exceed World Meteorological Organization (WMO) standards, is being positioned as exceeding World Meteorological Organization (WMO) standards for environmental research of greenhouse gases — though the team has not yet announced a roadmap to commercialization.
The sensor is detailed in the journal Sensors and Actuators B: Chemical, under closed-access terms.