(422e) Design of Heterogeneous Catalysts for High Temperature Electrochemical Reduction of CO2

The high levels of carbon dioxide (CO₂) emissions, consequential from the extensive use of fossil fuels, are major contemporary challenges. An approach to alleviate this process is to activate the reverse chemical pathways in which CO₂ is reduced into high-energy molecules. The electrochemical reduction of CO₂ to CO has attracted increasing attention, since CO represents a valuable intermediate to the production of synthetic fuels using established processes, such as Fischer-Tropsch. The use of solid oxide electrolysis cells (SOECs) to electrochemically reduce CO₂ to CO is an attractive technology, given that this solid-state electrochemical systems can, in principle, facilitate the CO₂ reduction with potentially very high rates due to the favorable kinetics at high operating temperatures. While electrochemical reduction of CO₂ using SOECs offers a great deal of promise, these systems are still limited by the high activation overpotential losses induced by the sluggish kinetics of CO₂ reduction at the cathode. In the present work, we combine experimental and theoretical techniques to understand the chemical/electrochemical process that governs CO₂ electrolysis, and develop a structure/performance relation in order to identify the optimum electrocatalyst for this process. Controlled electrochemical experiments show that upon modification of the electrode metal electrocatalyst, significant decrease in the overpotential is achieved. 

 

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