Covalent organic frameworks (COFs) are crystalline and porous organic materials attractive for photocatalysis applications due to their structural versatility and tunable optical and electronic properties. The use of photocatalysts (PCs) for polymerizations enables the preparation of well-defined polymeric materials under mild reaction conditions. Herein, we report two porphyrin-based donor–acceptor COFs that are effective heterogeneous PCs for photoinduced electron transfer-reversible addition–fragmentation chain transfer (PET-RAFT). Using density functional theory (DFT) calculations, we designed porphyrin COFs with strong donor–acceptor characteristics and delocalized conduction bands. The COFs were effective PCs for PET-RAFT, successfully polymerizing a variety of monomers in both organic and aqueous media using visible light (λ_max from 460 to 635 nm) to produce polymers with tunable molecular weights (MWs), low molecular weight dispersity, and good chain-end fidelity. The heterogeneous COF PCs could also be reused for PET-RAFT polymerization at least 5 times without losing photocatalytic performance. This work demonstrates porphyrin-based COFs that are effective catalysts for photo-RDRP and establishes design principles for the development of highly active COF PCs for a variety of applications.

中文翻译：

---

基于卟啉的供体-受体COFs作为广谱激发下PET-RAFT聚合的高效且可重复使用的光催化剂

共价有机框架 (COF) 是结晶和多孔有机材料，由于其结构的多功能性和可调节的光学和电子特性，对光催化应用具有吸引力。使用光催化剂 (PC) 进行聚合可以在温和的反应条件下制备定义明确的聚合物材料。在此，我们报告了两种基于卟啉的供体-受体 COF，它们是用于光诱导电子转移可逆加成断裂链转移 (PET-RAFT) 的有效异质 PC。使用密度泛函理论 (DFT) 计算，我们设计了具有强供体-受体特性和离域导带的卟啉 COF。COF 是 PET-RAFT 的有效 PC，使用可见光成功聚合了有机和水性介质中的多种单体（λ _max从 460 到 635 nm），以生产具有可调分子量 (MW)、低分子量分散性和良好链端保真度的聚合物。多相 COF PC 也可以重复用于 PET-RAFT 聚合至少 5 次而不会失去光催化性能。这项工作证明了卟啉基 COF 是光 RDRP 的有效催化剂，并为开发用于各种应用的高活性 COF PC 建立了设计原则。