Approaching Theoretical Performances of Electrocatalytic Hydrogen Peroxide Generation by Cobalt‐Nitrogen Moieties

Electrocatalytic oxygen reduction reaction (ORR) has been intensively studied for environmentally benign applications. However, insufficient understanding of ORR 2 e−‐pathway mechanism at the atomic level inhibits rational design of catalysts with both high activity and selectivity, causing concerns...

Full description

Saved in:
Bibliographic Details
Published in:Angewandte Chemie 2023-05, Vol.135 (21), p.n/a
Main Authors: Lin, Runjia, Kang, Liqun, Lisowska, Karolina, He, Weiying, Zhao, Siyu, Hayama, Shusaku, Hutchings, Graham J., Brett, Dan J. L., Corà, Furio, Parkin, Ivan P., He, Guanjie
Format: Article
Language:English
Subjects:
Carbon nanotubes
Catalysts
Chemical reduction
Chemistry
Cobalt
Cobalt-Nitrogen Moieties
Electrocatalyst
Electrocatalysts
Electrochemistry
Electron transfer
Hybrids
Hydrogen Peroxide
Oxygen Reduction Reaction
Oxygen reduction reactions
Citations: Items that this one cites
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Electrocatalytic oxygen reduction reaction (ORR) has been intensively studied for environmentally benign applications. However, insufficient understanding of ORR 2 e−‐pathway mechanism at the atomic level inhibits rational design of catalysts with both high activity and selectivity, causing concerns including catalyst degradation due to Fenton reaction or poor efficiency of H2O2 electrosynthesis. Herein we show that the generally accepted ORR electrocatalyst design based on a Sabatier volcano plot argument optimises activity but is unable to account for the 2 e−‐pathway selectivity. Through electrochemical and operando spectroscopic studies on a series of CoNx/carbon nanotube hybrids, a construction‐driven approach based on an extended “dynamic active site saturation” model that aims to create the maximum number of 2 e− ORR sites by directing the secondary ORR electron transfer towards the 2 e− intermediate is proven to be attainable by manipulating O2 hydrogenation kinetics. A series of CoNx/carbon nanotube hybrids as oxygen reduction electrocatalysts were studied through electrochemical and operando spectroscopic methods. When cathodically biased, a reconstruction in the symmetry of Co−Nx active sites is discovered, which leads to a shift in the electrocatalytic oxygen reduction reaction selectivity from producing water to hydrogen peroxide.
ISSN:0044-8249
1521-3757
DOI:10.1002/ange.202301433