Published on : Oct 13, 2017
The electrochemical reduction of carbon dioxide (CO2) has generated vast interests among scientists and engineers for the large scale storage of renewable and production of hydrocarbon fuels. The reduction of CO2 to carbon monoxide (CO) and hydrogen (H2) enables the chemical storage of solar energy. Investigators in search for an advanced mechanism and bringing improvements in electrochemical cell performance focus on different approaches and models, the discovery of an efficient electrocatalyst being a crucial one. A team of researchers affiliated with University of Illinois at Chicago and the Joint Center for Artificial Photosynthesis, Berkeley have discovered a mechanism that use electrocatalysts to convert carbon dioxide to carbon monoxide with the help of water and electricity. The process can prove to be a potential source of producing synthetic gas (syngas), a useful fuel gas mixture of carbon monoxide, carbon dioxide, and hydrogen.
Their work is detailed in a paper published online on October 2 in the journal Proceedings of the National Academy of Sciences.
Varying Voltage in Cell with Silver as Electrocatalysts Leads to Efficient CO Production
Researchers developed a multi-scale model for integrating density functional theory and transport models to better understand electrocatalytic reaction pathways in electrochemical cells. The model was developed by two of the researchers after intensively working for over a year and they used it for full-scale simulation of the reaction. For the production of carbon monoxide, an understanding of the structure of the catalysts used and their operating conditions is vital. The scientists found that the production of CO essentially depends on the applied electric potential and pressure of carbon dioxide in the cell. Controlling these factors can lead to an efficient production of CO.
Since the mixture of CO and H2 can be easily separated from the aqueous electrolyte solution, the electrochemical reaction can be used to produce syngas in large amounts, which can be converted into hydrocarbon fuels. Furthermore, the researchers found that various electrocatalysts such as gold, silver, zinc, gallium, and palladium can be used to obtain the varying ratios of CO and H2, with silver holding great promise owing to it being inexpensive and more abundant than others.