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Title: Tuning Two‐Electron Oxygen‐Reduction Pathways for H 2 O 2 Electrosynthesis via Engineering Atomically Dispersed Single Metal Site Catalysts
Abstract

The hydrogen peroxide (H2O2) generation via the electrochemical oxygen reduction reaction (ORR) under ambient conditions is emerging as an alternative and green strategy to the traditional energy‐intensive anthraquinone process and unsafe direct synthesis using H2and O2. It enables on‐site and decentralized H2O2production using air and renewable electricity for various applications. Currently, atomically dispersed single metal site catalysts have emerged as the most promising platinum group metal (PGM)‐free electrocatalysts for the ORR. Further tuning their central metal sites, coordination environments, and local structures can be highly active and selective for H2O2production via the 2eORR. Herein, recent methodologies and achievements on developing single metal site catalysts for selective O2to H2O2reduction are summarized. Combined with theoretical computation and advanced characterization, a structure–property correlation to guide rational catalyst design with a favorable 2eORR process is aimed to provide. Due to the oxidative nature of H2O2and the derived free radicals, catalyst stability and effective solutions to improve catalyst tolerance to H2O2are emphasized. Transferring intrinsic catalyst properties to electrode performance for viable applications always remains a grand challenge. The key performance metrics and knowledge during the electrolyzer development are, therefore, highlighted.

 
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NSF-PAR ID:
10367942
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Materials
Volume:
34
Issue:
23
ISSN:
0935-9648
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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