Water as a Promoter and Catalyst for Dioxygen Electrochemistry in Aqueous and Organic Media

Journal Article · Fri Oct 16 00:00:00 EDT 2015 · ACS Catalysis

DOI:https://doi.org/10.1021/acscatal.5b01779· OSTI ID:1223600

Staszak-Jirkovský, Jakub ^[1]; Subbaraman, Ram ^[2]; Strmcnik, Dusan ^[1]; Harrison, Katharine L. ^[3]; Diesendruck, Charles E. ^[4]; Assary, Rajeev ^[1]; Frank, Otakar ^[5]; Kobr, Lukáš ^[6]; Wiberg, Gustav K. H. ^[2]; Genorio, Bostjan ^[7]; Connell, Justin G. ^[1]; Lopes, Pietro P. ^[1]; Stamenkovic, Vojislav R. ^[1]; Curtiss, Larry ^[1]; Moore, Jeffrey S. ^[4]; Zavadil, Kevin R. ^[3]; Markovic, Nenad M. ^[1]

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1. Materials Science Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439, United States, Joint Center for Energy Storage Research, Argonne National Laboratory, 9700 S Cass Avenue, Argonne, Illinois 60439, United States
2. Materials Science Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439, United States
3. Sandia National Laboratory, P.O. Box 5800, Albuquerque, New Mexico 87185, United States, Joint Center for Energy Storage Research, Argonne National Laboratory, 9700 S Cass Avenue, Argonne, Illinois 60439, United States
4. University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States, Joint Center for Energy Storage Research, Argonne National Laboratory, 9700 S Cass Avenue, Argonne, Illinois 60439, United States
5. Department of Electrochemical Materials, J. Heyrovsky Institute of Physical Chemistry, Prague, Czech Republic
6. Northwestern University, Evanston, Illinois 60208, United States
7. Materials Science Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439, United States, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ljubljana, Slovenia, Joint Center for Energy Storage Research, Argonne National Laboratory, 9700 S Cass Avenue, Argonne, Illinois 60439, United States

Water and oxygen electrochemistry lies at the heart of interfacial processes controlling energy transformations in fuel cells, electrolyzers, and batteries. Here, by comparing results for the ORR obtained in alkaline aqueous media to those obtained in ultradry organic electrolytes with known amounts of H₂O added intentionally, we propose a new rationale in which water itself plays an important role in determining the reaction kinetics. This effect derives from the formation of HO_ad···H₂O (aqueous solutions) and LiO₂···H₂O (organic solvents) complexes that place water in a configurationally favorable position for proton transfer to weakly adsorbed intermediates. We also find that, even at low concentrations (<10 ppm), water acts simultaneously as a promoter and as a catalyst in the production of Li₂O₂, regenerating itself through a sequence of steps that include the formation and recombination of H⁺ and OH^–. We conclude that, although the binding energy between metal surfaces and oxygen intermediates is an important descriptor in electrocatalysis, understanding the role of water as a proton-donor reactant may explain many anomalous features in electrocatalysis at metal–liquid interfaces

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL (United States); Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: AC02-06CH11357; AC04-94AL85000
• OSTI ID: 1223600
• Alternate ID(s): OSTI ID: 1249103; OSTI ID: 1343272; OSTI ID: 1365808
• Report Number(s): SAND-2014-18453J; SAND-2017-1617J
• Journal Information: ACS Catalysis, Journal Name: ACS Catalysis Vol. 5 Journal Issue: 11; ISSN 2155-5435
• Publisher: American Chemical Society
• Country of Publication: United States
• Language: English

Related Subjects

batteries
lithium-oxygen
oxygen reduction reaction
activated water
electrocatalysis
water networks
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
lithium−oxygen