From Thick Air: Transforming CO2 into Light-Emitting Carbon
Researchers at the University of Ottawa have discovered a way to convert carbon dioxide gas (or CO2) into solid carbon forms that emit light. This new low-energy CO 2-reduction pathway for stable carbon has implications in many areas.
To learn more, we spoke to Dr. JaspreetWalia, a Post-Doctoral Fellow at the School of Electrical Engineering and Computer Science, and Dr. Pierre Berini (uOttawa Distinguished professor and University Research Chair for Surface Plasmon Photonics), the lead author.
Tell us about the discovery of your team.
Pierre Berini “We reduced carbon dioxide, a greenhouse gas, to solid carbon on a nanostructured silver substrate illuminated with green lights, without any other reagents. Energetic electrons excited by a green light on the silver surface transfer to carbon dioxide molecules and initiate dissociation. Photoluminescence is also a process that produces intense yellow light from carbon deposits.
This photo shows light emission. It is a process called photoluminescence. The light comes from solid carbon formed on a silver nanostructure. It is illuminated by green light. Credit: University of Ottawa. OSA Optica
How did these conclusions come about?
Jaspreet Wila: We used a technique called Raman Scattering to monitor the reaction in real-time to see which products were forming. We were surprised to see signs of carbon formation on the surface and bright, visible yellow light from the sample.
Why is it important?
Pierre Berini “Recently, there has been a lot of global research to develop technologies that can convert CO2 using visible lighting. This work proves that it is possible to create light-emitting solid carbon.
How can this discovery be applied to our daily lives?
Jaspreet Wialia: “This path for reagentless CO 2 reduction of light emitting carbon will be of interest to those involved in developing and applying industrial-scale catalytic processes and light-emitting metasurfaces.”
“Consequently, concerning the creation of carbon directly from CO2 gas, my findings will affect research involving plasma-assisted reactions. I expect the emergence of applications in the oil-and-gas industries, where catalytic conversions involving carbon-based compounds are a key focus area.
“Next-generation reactions that involve CO2 light could also result in other valuable outcomes such as artificial photosynthesis. The light-emitting component of our discovery could allow for light control and manipulation at nanoscales and the possibility of flat light sources. Catalysis is also possible using nanostructured carbon.
“Finally, the wavelength (or color) of light emitted by carbon dots on a surface of silver could be highly sensitive to the surrounding environment. This makes it an attractive platform for pollutant detection, such as lead.
Do you have any suggestions?
Pierre Berini “We have discovered how to create solid carbon deposits that emit light” “out of thick Air,” thanks to the light-assisted conversion of CO 2 gas driven with energetic electrons. This project was driven entirely by curiosity and had no expectations. It also benefited from close collaboration with Sabaa Rashid, Graham Killaire, Professors Fabio Variola, and Arnaud Youck.
