Oxygen Isotopologues Resolved from Water Oxidation Electrocatalysis by Electron Paramagnetic Resonance Spectroscopy.
J Am Chem Soc
; 146(22): 15019-15026, 2024 Jun 05.
Article
in En
| MEDLINE
| ID: mdl-38743719
ABSTRACT
Electrocatalytic water oxidation is a key transformation in many strategies designed to harness solar energy and store it as chemical fuels. Understanding the mechanism(s) of the best electrocatalysts for water oxidation has been a fundamental chemical challenge for decades. Here, we quantitate evolved dioxygen isotopologue composition via gas-phase EPR spectroscopy to elucidate the mechanisms of water oxidation on metal oxide electrocatalysts with high precision. Isotope fractionation is paired with computational and kinetic modeling, showing that this technique is sensitive enough to differentiate O-O bond-forming steps. Strong agreement between experiment and theory indicates that for the nickel-iron layered double hydroxideâone of the best earth-abundant electrocatalysts to be studiedâwater oxidation proceeds via a dioxo coupling mechanism to form a side-bound peroxide rather than a hydroxide attack to form an end-bound peroxide.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
J Am Chem Soc
/
Journal of the american chemical society
/
J. am. chem. soc
Year:
2024
Document type:
Article
Affiliation country:
United States
Country of publication:
United States