Oxygen-tolerant CO2 electroreduction over covalent organic frameworks via photoswitching control oxygen passivation strategy

• Published in: Nature communications 2024-02, Vol.15 (1), p.1479-1479, Article 1479
• Main Authors: Zhu, Hong-Jing, Si, Duan-Hui, Guo, Hui, Chen, Ziao, Cao, Rong, Huang, Yuan-Biao
• Format: Article
• Language: English
• Subjects: 639/301/299/161; 639/4077/909; 639/638/549/941; 639/638/77/886; Aerobic conditions; Carbon dioxide; Chemical reduction; Cobalt; Covalence; Cyclopentene; Electrocatalysts; Electrochemistry; Electrowinning; Flue gas; Humanities and Social Sciences; Irradiation; multidisciplinary; Oxygen; Oxygen reduction reactions; Passivity; Porphyrins; Power plants; Science; Science (multidisciplinary); Ultraviolet radiation
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-024-45959-9

The direct use of flue gas for the electrochemical CO 2 reduction reaction is desirable but severely limited by the thermodynamically favorable oxygen reduction reaction. Herein, a photonicswitching unit 1,2-Bis(5’-formyl-2’-methylthien-3’-yl)cyclopentene (DAE) is integrated into a cobalt porphyrin-based covalent organic framework for highly efficient CO 2 electrocatalysis under aerobic environment. The DAE moiety in the material can reversibly modulate the O 2 activation capacity and electronic conductivity by the framework ring-closing/opening reactions under UV/Vis irradiation. The DAE-based covalent organic framework with ring-closing type shows a high CO Faradaic efficiency of 90.5% with CO partial current density of −20.1 mA cm −2 at −1.0 V vs. reversible hydrogen electrode by co-feeding CO 2 and 5% O 2 . This work presents an oxygen passivation strategy to realize efficient CO 2 electroreduction performance by co-feeding of CO 2 and O 2 , which would inspire to design electrocatalysts for the practical CO 2 source such as flue gas from power plants or air. Direct use of flue gas for the electrocatalytic CO 2 reduction reaction is desirable but severely limited by the thermodynamically favorable oxygen reduction reaction. Here the authors report an oxygen passivation strategy to improve electrocatalytic CO 2 reduction reaction under aerobic conditions using a covalent organic frameworks with a photoswitching unit.