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Title: Dynamic Promotion of the Oxygen Evolution Reaction via Programmable Metal Oxides
Hydrogen gas is a promising renewable energy storage medium when produced via water electrolysis, but this process is limited by the sluggish kinetics of the anodic oxygen evolution reaction (OER). Herein, we used a microkinetic model to investigate promoting the OER using programmable oxide catalysts (i.e., forced catalyst dynamics). We found that programmable catalysts could increase current density at a fixed overpotential (100-600× over static rates) or reduce the overpotential required to reach a fixed current density of 10 mA cm-2 (45-140% reduction vs static). In our kinetic parametrization, the key parameters controlling the quality of the catalytic ratchet were the O*-to-OOH* and O*-to-OH* activation barriers. Our findings indicate that programmable catalysts may be a viable strategy for accelerating the OER or enabling lower-overpotential operation, but a more accurate kinetic parametrization is required for precise predictions of performance, ratchet quality, and resulting energy efficiency.  more » « less
Award ID(s):
2152119
PAR ID:
10522754
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
ACS Energy Letters
Date Published:
Journal Name:
ACS Energy Letters
Volume:
9
Issue:
5
ISSN:
2380-8195
Page Range / eLocation ID:
2013 to 2023
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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