Revealing the structure–activity relationship in woven covalent organic frameworks for the electrocatalytic oxygen reduction reaction†
Abstract
Woven covalent organic frameworks (COFs) possess three-dimensional (3D) frameworks with well-dispersed variable metal centers, showing great promise in heterogeneous catalysis. Until now, woven COFs have not been exploited as catalysts. Herein, COF-112 (a typical woven COF) is utilized as an ORR catalyst to reveal the role of the metal center and linkage. Through metal center variation, the optimal COF-112Co with imine linkage exhibits superior ORR activity (Eonset = 0.87 V vs. RHE, n = 3.86, and JL = 5.78 mA cm−2). Experimental and theoretical studies demonstrate the non-metallic ORR active site and confirm the influence of metal variation in COF-112. A linkage conversion strategy reveals the importance of the imine linkage on the 4e− ORR. This work reveals the structure–activity relationship of woven COFs, which will broaden the application of COFs and extend the diversity of electrocatalysts.