Scientists from Russia and the Czech Republic found a new, plasmon energy-based method to synthesise cyclic carbonates from atmospheric carbon dioxide. The reaction was carried out under sunlight and at room temperature, in contrast to conventional methods that require synthesis under high pressure and temperature. The research conducted by the Tomsk Polytechnic University in cooperation with the University of Chemistry and Technology of Prague and the Jan Evangelista Purkyne University was published in the Journal of Materials Chemistry.
“The increase in CO2 levels in the atmosphere is a global environmental problem,” started Olga Guselnikova, Research Fellow of the TPU Research School of Chemistry and Applied Biomedical Sciences and one of the authors of the research. “The solutions of the problem are usually focused on measures to reduce CO2 emissions, an alternative method is to use the CO2 already existing in the atmosphere for useful chemical transformations.”
Ms Guselinkova explained that the new method allows obtaining widely sought-after cyclic carbonates under sunlight. Cyclic carbonates are organic compounds, used as electrolytes for lithium-ion batteries, green solvents as well as in pharmaceutical drugs manufacturing. The scientists managed to synthesize carbonates under sunlight and at room temperature. With conventional methods, such reactions have been carried out only at high temperatures ranging from 60°С to 150°С and high CO2 pressure up to 25 atm.
“It means the technological chain requires additional equipment for CO2 compression and heating, in other words, it is impossible to simply extract it from the air,” said Ms Guselnikova.
As a result of the experiments, the scientists synthesised cyclic carbonates from the interaction of CO2 and epoxides, used as starting materials. Then they irradiated this mixture with infrared light. As the authors of the article note, the synthesis process is comparable with similar methods, however, it does not require special technologically sophisticated equipment.
“The most important is to demonstrate an opportunity to conduct the reaction directly with the air without prior purification or CO2 concentration under ambient conditions and sunlight,” said Pavel Postnikov, Associate Professor of the TPU Research School of Chemistry and Applied Biomedical Sciences adding that ultimately, it makes the synthesis more simple and eco-friendly.