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This content will become publicly available on December 1, 2023

Title: CO2/carbonate-mediated electrochemical water oxidation to hydrogen peroxide
Abstract Electrochemical water oxidation reaction (WOR) to hydrogen peroxide (H 2 O 2 ) via a 2e − pathway provides a sustainable H 2 O 2 synthetic route, but is challenged by the traditional 4e − counterpart of oxygen evolution. Here we report a CO 2 /carbonate mediation approach to steering the WOR pathway from 4e − to 2e − . Using fluorine-doped tin oxide electrode in carbonate solutions, we achieved high H 2 O 2 selectivity of up to 87%, and delivered unprecedented H 2 O 2 partial currents of up to 1.3 A cm −2 , which represents orders of magnitude improvement compared to literature. Molecular dynamics simulations, coupled with electron paramagnetic resonance and isotope labeling experiments, suggested that carbonate mediates the WOR pathway to H 2 O 2 through the formation of carbonate radical and percarbonate intermediates. The high selectivity, industrial-relevant activity, and good durability open up practical opportunities for delocalized H 2 O 2 production.
Authors:
; ; ; ; ; ; ; ; ;
Award ID(s):
1900039
Publication Date:
NSF-PAR ID:
10352259
Journal Name:
Nature Communications
Volume:
13
Issue:
1
ISSN:
2041-1723
Sponsoring Org:
National Science Foundation
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