Circumventing Scaling Relations in Oxygen Electrochemistry Using Metal-Organic Frameworks

Tyler Sours, Anjli Patel, Jens Nørskov, Samira Siahrostami*, Ambarish Kulkarni*

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

It has been well-established that unfavorable scaling relationships between *OOH, *OH, and *O are responsible for the high overpotentials associated with oxygen electrochemistry. A number of strategies have been proposed for breaking these linear constraints for traditional electrocatalysts (e.g., metals, alloys, metal-doped carbons); such approaches have not yet been validated experimentally for heterogeneous catalysts. Development of a new class of catalysts capable of circumventing such scaling relations remains an ongoing challenge in the field. In this work, we use density functional theory (DFT) calculations to demonstrate that bimetallic porphyrin-based MOFs (PMOFs) are an ideal materials platform for rationally designing the 3-D active site environments for oxygen reduction reaction (ORR). Specifically, we show that the *OOH binding energy and the theoretical limiting potential can be optimized by appropriately tuning the transition metal active site, the oxophilic spectator, and the MOF topology. Our calculations predict theoretical limiting potentials as high as 1.07 V for Fe/Cr-PMOF-Al, which exceeds the Pt/C benchmark for 4e ORR. More broadly, by highlighting their unique characteristics, this work aims to establish bimetallic porphyrin-based MOFs as a viable materials platform for future experimental and theoretical ORR studies.
Original languageEnglish
JournalJournal of Physical Chemistry Letters
Volume11
Pages (from-to)10029-10036
ISSN1948-7185
DOIs
Publication statusPublished - 2020

Fingerprint Dive into the research topics of 'Circumventing Scaling Relations in Oxygen Electrochemistry Using Metal-Organic Frameworks'. Together they form a unique fingerprint.

Cite this