Carbon dioxide, a byproduct of burning fossil fuels, is the primary greenhouse gas responsible for 78% of the change in energy balance in Earth’s atmosphere between 1990 and 2022. This harmful gas enters the atmosphere from sources such as car exhaust and coal-fired power plants. While even renewable energy resources produce some carbon dioxide, it is at a much lower level compared to coal and natural gas emissions. Researchers are exploring ways to utilize carbon dioxide through a process called electrochemical carbon dioxide reduction (CO2R) to convert it into clean fuels and useful chemicals.
In a recent study published in Nature Catalysis, researchers from the UChicago Pritzker School of Molecular Engineering’s Amanchukwu Lab presented a method to make CO2R more efficient by manipulating water molecules. The goal is to create a clean energy loop where carbon dioxide can be converted back into fuels using green electricity from sources like solar and wind. The team was able to achieve nearly 100% efficiency in CO2R under mildly acidic conditions using either gold or zinc as catalysts. This innovation could lead to more sustainable energy production and reduce the reliance on fossil fuels.
During the CO2R process, researchers use electricity and water to break up and rearrange the carbon dioxide molecules to form other, more desirable molecules that can be used as fuels or chemicals. However, stable pairings of hydrogen atoms often form, known as the hydrogen evolution reaction (HER), making CO2R less efficient. By controlling the water behavior using organic solvents and acid additives, the Amanchukwu Lab was able to minimize HER and optimize the creation of desired molecules. This approach could improve the overall efficiency of CO2R and reduce the unwanted byproducts.
Many efficient methods for CO2R rely on precious metals like platinum, silver, and gold as catalysts, but these materials can be expensive for industrial applications. By engineering the electrolyte, the researchers developed a new method that can achieve similar results using cheaper, more abundant materials like zinc. This breakthrough allows for the use of earth-abundant metals in CO2R processes, making the overall process more cost-effective and accessible for widespread utilization. The ability to control water behavior in CO2R opens up new possibilities for sustainable energy production.
The Amanchukwu Lab’s innovative approach to CO2R has been recognized by the American Chemical Society, naming Chibueze Amanchukwu as one of its “Talented Twelve” young scientists who are contributing to the advancement of chemistry and making a positive impact on the world. By combining insights from aqueous batteries with CO2R research, the team has developed a method that shows promise in transforming carbon dioxide into valuable fuels and chemicals. With further development and implementation, this technology could play a significant role in reducing greenhouse gas emissions and transitioning towards a more sustainable energy future.
