Benchmarking of Heterogeneous CO2 Reduction Reaction Electrocatalysts

The identification of earth abundant, efficient electrocatalysts for the oxygen evolution reaction (OER), hydrogen evolution reaction (HER), and carbon dioxide reduction reaction (CO₂RR) is crucial for the development of solar-fuels devices.  Historically, procedures and conditions used for the evaluation of various electrocatalysts differ from laboratory to laboratory, resulting in performance metrics that are not easily compared. We have developed a benchmarking protocol that allows for the consistent assessment of activity, stability, electrochemically-active surface area and Faradaic efficiencies of electrocatalysts.  Using this benchmarking protocol, we have evaluated the performance of over 50 HER and OER electrocatalyts. The standardized evaluation of OER and HER electrocatalysts has allowed us to identify important trends for the advancement of solar-fuels research. More recently, we have developed electrochemical methods for the standardized analysis of electrocatalysts for CO₂RR. This has included the development of analytical methods for standardized identification and quantification of CO₂ reduction products. Given the complexity of CO₂ reduction reactions and the variety of products that can be formed depending upon the catalyst, product analysis plays a key role on the Benchmarking of CO₂ reduction catalysts. Herein, we present benchamrking of CO₂RR catalysts and the analytical methods developed for the identification and quantification of liquid and gaseous products.