Birgitta Schultze-Bernhardt (2nd from right) and her team at the world's first broadband UV dual-comb spectrometer. Credit: Lunghammer - NAWI Graz
Researchers from the Institute of Experimental Physics at Graz University of Technology (TU Graz) have developed the first broadband UV dual-comb spectrometer to enhance environmental monitoring capabilities. Utilizing the new technology, researchers can continually monitor air pollutants and observe their reaction with the environment in real-time.
Published in the journal Optica, the novel spectrometer relies on the high reaction potential of UV light when interacting with nitrogen oxides at ground level. Traditional dual-comb spectrometers utilize a source light to emit at a broad wavelength and detect the alteration of these wavelengths when passing through a gaseous sample. In the spectrometer developed by the researchers, a laser system is employed to emit double pulses within the ultraviolet spectrum.
When the ultraviolet light emitted encounters a gas molecule, it excites the molecule and causes rovibronic transitions that are unique to each gas. Additionally, the spectrometer offers a large bandwidth of UV light, high spectral resolution, and rapid measurement times.
“This makes our spectrometer suitable for sensitive measurements by which changes in gas concentrations and the course of chemical reactions can be observed very precisely,” said Lukas Fürst, first author of the study.
To develop and test the spectrometer, the team used formaldehyde, a common air pollutant produced when wood or fossil fuels are burned. “With our new spectrometer, formaldehyde emissions in the textile or wood processing industries as well as in cities with increased smog levels can be monitored in real time, thus improving the protection of personnel and the environment,” said Birgitta Schultze-Bernhardt, the leader of the research team.
The spectrometer has a wide range of potential applications and the team hopes this will bring to light the effects of other common air pollutants such as nitrogen oxides and ozone. Additionally, the team believes the spectrometer could be used to develop new strategies for air pollution remediation in the future.