Three‐dimensional covalent organic frameworks (3D COFs), recognized for their tailorable structures and accessible active sites, offer a promising platform for developing advanced photocatalysts. However, the difficulty in the synthesis and functionalization of 3D COFs hinders their further development. In this study, we present a series of 3D‐bcu‐COFs with 8 connected porphyrin units linked by linear linkers through imine bonds as a versatile platform for photocatalyst design. The photoresponse of 3D‐bcu‐COFs was initially modulated by functionalizing linear linkers with benzo‐thiadiazole or benzo‐selenadiazole groups. Furthermore, taking advantage of the well‐exposed porphyrin and imine sites in 3D‐bcu‐COFs, their photocatalytic activity was optimized by stepwise protonation of imine bonds and porphyrin centers. The dual protonated COF with benzo‐selenadiazole groups exhibited enhanced charge separation, leading to an increased photocatalytic H2O2 production under visible light. This enhancement demonstrates the combined benefits of linker functionalization and stepwise protonation on photocatalytic efficiency.

中文翻译：

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三维共价有机框架的逐步质子化增强过氧化氢光合作用

三维共价有机框架（3D COF）以其可定制的结构和可接近的活性位点而闻名，为开发先进的光催化剂提供了一个有前途的平台。然而，3D COF的合成和功能化的困难阻碍了其进一步发展。在这项研究中，我们提出了一系列具有 8 个连接的卟啉单元的 3D-bcu-COF，这些单元通过亚胺键由线性连接体连接，作为光催化剂设计的多功能平台。 3D-bcu-COF 的光响应最初是通过用苯并噻二唑或苯并硒二唑基团功能化线性连接基来调节的。此外，利用3D-bcu-COF中充分暴露的卟啉和亚胺位点，通过亚胺键和卟啉中心的逐步质子化优化其光催化活性。具有苯并硒二唑基团的双质子化 COF 表现出增强的电荷分离，导致可见光下光催化 H2O2 产量增加。这种增强证明了连接基功能化和逐步质子化对光催化效率的综合优势。