Construction of Fully Conjugated Covalent Organic Frameworks via Facile Linkage Conversion for Efficient
Yuancheng Wang1, Hui Liu1, Qingyan Pan1
1Key Laboratory of Biobased Polymer Materials, Shandong Provincial Education Department, College of Polymer Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042, China.
Abstract:
Covalent organic frameworks (COFs) with improved stability and extended π-conjugation structure are highly desirable. Here, two imine-linked COFs were converted into ultrastable and π-conjugated fused-aromatic thieno[3,2-c]pyridine-linked COFs (B-COF-2 and T-COF-2). The successful conversion was confirmed by infrared and solid-state 13C NMR spectroscopies. Furthermore, the structures of thieno[3,2-c]pyridine-linked COFs were evaluated by TEM and PXRD. It is noted that a slight difference in the structure leads to totally different photoactivity. The fully π-conjugated T-COF-2 containing triazine as the core exhibited an excellent photocatalytic NADH regeneration yield of 74% in 10 min.
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