Ma Xiaolin, Hu Jingyue, Li Senzhi, Zheng Tianyu, Gao Ying, Han Yuesheng, Pan Houhe, Bian Yongzhong, Jiang Jianzhuang
Beijing Advanced Innovation Center for Materials Genome Engineering, Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline Materials, Department of Chemistry and Chemical Engineering, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing 100083, China.
Beijing Advanced Innovation Center for Materials Genome Engineering, Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline Materials, Department of Chemistry and Chemical Engineering, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing 100083, China.
Sci Bull (Beijing). 2025 Jul 30;70(14):2277-2284. doi: 10.1016/j.scib.2025.04.002. Epub 2025 Apr 2.
Two-dimensional (2D) porphyrin (Por)-based covalent organic frameworks (COFs) provide an attractive and effective strategy for photocatalytic CO reduction, but the layered structure due to π-π stacking is challenging for the exposure of active sites and transfer of mass and photogenerated carriers. In this study, a series of 2D conjugated porphyrin-based COFs were prepared using porphyrin blocks with linking units having different degrees of twisting. According to the experimental and theoretical calculation results, owing to the large spatial steric hindrance between the two carbazole units connected by the N-N single bond, a greatly undulating layered structure was formed in NN-Por-COF, which enhanced mass transfer and exposed more catalytic sites. The introduction of carbazole also modulated the electronic structure of the porphyrin Co center, which lowered the reaction energy barrier. The optimization of the structural and electronic effects led to the excellent photocatalytic CO reduction performance of NN-Por-COF, with CO conversion rates as high as 22.38 and 3.02 mmol g h under pure and diluted (10%) CO atmosphere, respectively, which are superior to those of most of the reported porphyrin-based photocatalysts.
二维（2D）卟啉基共价有机框架（COF）为光催化CO还原提供了一种有吸引力且有效的策略，但由于π-π堆积导致的层状结构对于活性位点的暴露以及质量和光生载流子的转移具有挑战性。在本研究中，使用具有不同扭曲程度连接单元的卟啉砌块制备了一系列二维共轭卟啉基COF。根据实验和理论计算结果，由于通过N-N单键连接的两个咔唑单元之间存在较大的空间位阻，在NN-Por-COF中形成了高度起伏的层状结构，这增强了传质并暴露了更多催化位点。咔唑的引入还调节了卟啉Co中心的电子结构，降低了反应能垒。结构和电子效应的优化导致NN-Por-COF具有优异的光催化CO还原性能，在纯CO气氛和稀释（10%）CO气氛下，CO转化率分别高达22.38和3.02 mmol g⁻¹ h⁻¹，优于大多数已报道的卟啉基光催化剂。
