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Single atom catalysts (SACs) have been widely studied in the field of CO2 electroreduction, but industrial‐level current density and near‐unity product selectivity are still difficult to achieve. Herein, a diatomic site catalysts (DASCs) consisting of Co‐Cu hetero‐diatomic pairs is synthesized. The CoCu DASC exhibits excellent selectivity with the maximum CO Faradaic efficiency of 99.1 %. The CO selectivity can maintain above 95 % over a wide current density range from 100 mA cm−2 to 500 mA cm−2. The maximum CO partial current density can reach to 483 mA cm−2 in flow cell, far exceed industrial‐level current density requirements (>200 mA cm−2). Theoretical calculation reveals that the synergistic catalysis of the Co‐Cu bimetallic sites reduce the activation energy and promote the formation of intermediate *COOH. This work shows that the introduction of another metal atom into SACs can significantly affect the electronic structure and then enhance the catalytic activity of SACs. [ABSTRACT FROM AUTHOR]

Metal N- heterocyclic carbenes (M-NHCs) on the pore walls of a porous metal-organic framework (MOF) can be used as active sites for efficient organic catalysis. Traditional approaches that need strong alkaline reagents or insoluble Ag2O are not, however, suitable for the incorporation of NHCs on the backbones of MOFs because such reagents could destroy their frameworks or result in low reactivity. Accordingly, development of facile strategies toward functional MOFs with covalently bound M-NHCs for catalysis is needed. Herein, we describe the development of a general and facile approach to preparing MOFs with covalently linked active M-NHC (M = Pd, Ir) single-site catalysts by using a soluble Ag salt AgOC(CF3)3 as the source and subsequent transmetalation. The well-defined M-NHC-MOF (M = Pd, Ir) catalysts obtained in this way have shown excellent catalytic activity and stability in Suzuki reactions and hydrogen transfer reactions. This provides a general and facile strategy for anchoring functional M-NHC single-site catalysts onto functionalized MOFs for different reactions. [ABSTRACT FROM AUTHOR]

Abstract: Covalent triazine frameworks (CTFs) have emerged as one class of outstanding porous materials due to their abundant nitrogen sites and highly thermal and chemical stability. However, most of the reported CTFs are neutral porous materials. Here, we report the synthesis of the well‐designed cationic covalent triazine frameworks (CCTFs) via an ionothermal method from the imidazolium monomer 1,3‐bis(4‐cyanophenyl)imidazolium chloride. The imidazolium active sites and pore structure of CCTFs at different synthetic temperature were systematically investigated. The porous CCTFs with positively charged (imidazolium moieties) backbones could effectively adsorb and capture of CO2 through dipole–quadruple interactions. Furthermore, the positively charged imidazolium moieties and the spatially confined nucleophilic chloride anions works in concert on the substrate, leading to synergistically enhanced catalysis for the cycloaddition reaction of epoxide with CO2. These findings provide a new way to design and construct ionic porous materials for sustainable catalysis. [ABSTRACT FROM AUTHOR]