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Title: Combining scaling relationships overcomes rate vs. overpotential tradeoffs in O2 molecular electrocatalysis

Journal Article · · Science Advances

The development of advanced chemical-to-electrical energy conversions requires fast and efficient electrocatalysis of multi-electron/multi-proton reactions, such as the oxygen reduction reaction 10 (ORR). Using molecular catalysts, correlations between the reaction rate and energy efficiency have recently been identified. Improved catalysis requires circumventing the rate vs. overpotential tradeoffs implied by such ‘scaling relationships.’ Described here is an ORR system—using a soluble iron-porphyrin and weak acids—with the best reported combination of rate and efficiency for a soluble ORR catalyst. This advance is achieved not by “breaking” scaling relationships but 15 rather by combining two of them. Key to this behavior is a polycationic ligand, which enhances anionic ligand binding and changes the catalyst E1/2. These results show how combining scaling relationships is powerful way towards improved electrocatalysis.

Research Organization:
Energy Frontier Research Centers (EFRC) (United States). Center for Molecular Electrocatalysis (CME); Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)
Sponsoring Organization:
USDOE
DOE Contract Number:
AC05-76RL01830
OSTI ID:
1708857
Report Number(s):
PNNL-SA-146733
Journal Information:
Science Advances, Vol. 6, Issue 11; ISSN 2375-2548
Publisher:
AAAS
Country of Publication:
United States
Language:
English

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