Single-Atom Catalysts on Covalent Organic Frameworks for CO2 Reduction

The long-unresolved issue of CO2 release and the resulting atmospheric change can be solved through the application of effective catalysts. Thus, single-atom catalysts (SACs) have been rapidly developed for the CO2 reduction reaction (CO2RR), as they show improved catalytic metrics and enable the generation of C2+ products. Among numerous novel SACs, such as those based on graphene, metal–organic frameworks, and covalent organic frameworks (COFs), the COF-based SACs are the most promising owing to their high stability, porosity, and designability. Considering this, we describe two synthesis methods of COF-based SACs: ligand coordination and macrocycle backbone integration, and explore the pros and cons of each. We also propose routes for designing superior COF-based SACs and evaluate the factors influencing CO2RRs over COF-based SACs, such as metal loading and ligand types.