Implanting Numerous Hydrogen‐Bonding Networks in a Cu‐Porphyrin‐Based Nanosheet to Boost CH4 Selectivity in Neutral‐Media CO2 Electroreduction

• Published in: Angewandte Chemie Vol. 133; no. 40; pp. 22123 - 22129
• Main Authors: Wang, Yi‐Rong, Liu, Ming, Gao, Guang‐Kuo, Yang, Yi‐Lu, Yang, Ru‐Xin, Ding, Hui‐Min, Chen, Yifa, Li, Shun‐Li, Lan, Ya‐Qian
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 27.09.2021
• Subjects: Bonding; Carbon dioxide; Catalysts; Chemical reduction; Chemistry; Electrocatalysts; Electrochemistry; electroreduction; Hydrogen; hydrogen bonds; Methane; Nanosheets; Porphyrins; Protons; Selectivity
• ISSN: 0044-8249; 1521-3757
• DOI: 10.1002/ange.202108388

The exploration of novel systems for the electrochemical CO2 reduction reaction (CO2RR) for the production of hydrocarbons like CH4 remains a giant challenge. Well‐designed electrocatalysts with advantages like proton generation/transferring and intermediate‐fixating for efficient CO2RR are much preferred yet largely unexplored. In this work, a kind of Cu‐porphyrin‐based large‐scale (≈1.5 μm) and ultrathin nanosheet (≈5 nm) has been successfully applied in electrochemical CO2RR. It exhibits a superior FECH4 of 70 % with a high current density (−183.0 mA cm−2) at −1.6 V under rarely reported neutral conditions and maintains FECH4 >51 % over a wide potential range (−1.5 to −1.7 V) in a flow cell. The high performance can be attributed to the construction of numerous hydrogen‐bonding networks through the integration of diaminotriazine with Cu‐porphyrin, which is beneficial for proton migration and intermediate stabilization, as supported by DFT calculations. This work paves a new way in exploring hydrogen‐bonding‐based materials as efficient CO2RR catalysts. A Cu‐porphyrin‐based large‐scale, ultrathin nanosheet with numerous hydrogen‐bonding networks was developed for the highly selective electroreduction of CO2 to CH4 under neutral conditions. This catalyst exhibits a superior FECH4 of 70 % with a high current density (−183.0 mA cm−2) at −1.6 V under rarely reported neutral conditions and maintains FECH4 >51 % over a wide potential range (−1.5 to −1.7 V) in a flow cell.