Researchers from the US Department of Energy’s Argonne National Laboratory and the University of Illinois at Chicago created solar cells to transform carbon dioxide into a usable energy source using sunlight. The research team believes that these cells could be used in the form of artificial leaves that would produce fuel in a large scale and clean the atmosphere.
This experiment needed the use of a catalyst to allow the carbon dioxide to react more readily because this gas is chemically unreactive, making its conversion into something else difficult. Thus, they used tungsten diselenide, a metal compound that was shaped into nanosized flakes to expose its reactive edges and increase the surface area. They explain that this resembles the process in which plants use enzyme to convert atmospheric carbon dioxide into a sugar.
This process turned the carbon dioxide into carbon monoxide. Carbon monoxide is also a greenhouse gas but converting CO2 into this is more practical since scientists already know how to convert carbon monoxide into methanol and other usable fuel.
The team compares this process to photosynthesis. Consequently, the research team was able to create an artificial leaf that can transform carbon dioxide into fuel in three ways.
The researchers explain that photons from light are converted into pairs of negatively charged electrons as well as positively charged holes. These two then separate from each other.
The holes react with water molecules. This reaction results in the creation of protons and oxygen molecules.
The third step involves protons, electrons and carbon dioxide reacting together to produce carbon monoxide and water. The carbon monoxide can now be converted into usable fuel using known procedures.
Apparently, the reaction is very efficient. This lowers the energy cost to recycle carbon dioxide.
The findings are now stated in the study named “Nanostructured transition metal dichalcogenide electrocatalysts for CO2 reduction in ionic liquid.” The study is available in the journal Science.