Metal–Organic Framework Supported Low‐Nuclearity Cluster Catalysts for Highly Selective Carbon Dioxide Electroreduction to Ethanol

• Published in: Angewandte Chemie Vol. 136; no. 45
• Main Authors: Shao, Bing, Huang, Du, Huang, Rui‐Kang, He, Xing‐Lu, Luo, Yan, Xiang, Yi‐Lei, Jiang, Lin‐bin, Dong, Min, Li, Shixiong, Zhang, Zhong, Huang, Jin
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 04.11.2024
• Subjects: Absorption spectroscopy; Active sites; C2+ products; Carbon dioxide; carbon dioxide reduction; Catalysts; Chemical reduction; Chemical synthesis; Clusters; Density functional theory; electrocatalysis; Electrochemistry; Electrowinning; Ethanol; Infrared absorption; Infrared spectroscopy; low-nuclearity cluster; Metal-organic frameworks; Synergism
• ISSN: 0044-8249; 1521-3757
• DOI: 10.1002/ange.202409270

It is still a great challenge to achieve high selectivity of ethanol in CO2 electroreduction reactions (CO2RR) because of the similar reduction potentials and lower energy barrier of possible other C2+ products. Here, we report a MOF‐based supported low‐nuclearity cluster catalysts (LNCCs), synthesized by electrochemical reduction of three‐dimensional (3D) microporous Cu‐based MOF, that achieves a single‐product Faradaic efficiency (FE) of 82.5 % at −1.0 V (versus the reversible hydrogen electrode) corresponding to the effective current density is 8.66 mA cm−2. By investigating the relationship between the species of reduction products and the types of catalytic sites, it is confirmed that the multi‐site synergism of Cu LNCCs can increase the C−C coupling effect, and thus achieve high FE of CO2–to–ethanol. In addition, density functional theory (DFT) calculation and operando attenuated total reflectance surface‐enhanced infrared absorption spectroscopy further confirmed the reaction path and mechanism of CO2–to–EtOH. Cu‐based MOFs with unstable Cu coordination centers is electrochemically reduced to highly dispersed Cu subnanoclusters supported onto the remaining MOFs with 3D coordination bonds by the pore space limitation. The synergistic effect of Cu subnanoclusters promotes *CO−*CO coupling generation *CH2CHO species, leading to excellently electrocatalytic CO2–to–EtOH performance.