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DOE OSTI · 2460521

Optimizing Catalysis by Combining Molecular Scaling Relationships: Iron Porphyrin-Catalyzed Electrochemical Oxygen Reduction as a Case Study

Groff, Benjamin D.·Mayer, James M.
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Abstract

Here, the present work demonstrates the generality of molecular scaling relationships toward achieving faster catalysis at lower overpotentials. In iron porphyrin-catalyzed oxygen reduction, independent tuning of the catalyst E 1/2 and buffer pK a resulted in improvement of both the maximum turnover frequency (TOF max ) and the effective overpotential (η eff ). Interestingly, the most optimal system is achieved with the most reducing catalyst and a weak buffered acid—a perhaps counterintuitive conclusion. More generally, this study illustrates a path to optimization of catalytic systems through their differing responses to changes in the intrinsic features of the system.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYelectrocatalysisoxygen reduction reactionscaling relationships

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Groff, Benjamin D., Mayer, James M.. 2022-09-12. Optimizing Catalysis by Combining Molecular Scaling Relationships: Iron Porphyrin-Catalyzed Electrochemical Oxygen Reduction as a Case Study. https://doi.org/10.1021/acscatal.2c04190

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