Recent Advancements in COFs‐Based Heterostructures for CO₂ Photoreduction

Abstract Covalent–organic frameworks (COFs) based heterojunctions photocatalytic have showed great potential for CO 2 upcycling. Currently, significant progress has been made in developing such photocatalysts, yet a comprehensive understanding of this field remains lacking. This review systematically explores the inherent relationship between COF‐based heterojunction innovations and photocatalytic CO₂ reduction, aiming to establish a structure–performance–mechanism correlation that guides the design of high‐efficiency catalysts. First, the fundamentals, mechanisms, and related principles of photocatalytic CO 2 conversion, as well as the advantages of COFs in this application, are thoroughly introduced. Then, the state‐of‐the‐art COF‐based heterojunctions applied for photocatalytic CO 2 reduction are discussed from following critical aspects: interfacial engineering, spatial charge transfer regulation, active component hybridization, half‐reaction kinetic optimization, and active sites engineering. Subsequently, a systematic overview of characterization techniques and research methodologies for probing catalyst structures and in‐depth reaction mechanisms in this field is systematically outlined. Finally, the challenges and further development direction of COF‐based heterojunctions for CO 2 reduction are proposed. It is expected that this review can provide a powerful guidance and reference toward further exploiting high‐performance photocatalysts for CO 2 conversion.