Vinylene-Linked Woven Covalent Organic Frameworks for the Oxygen Reduction Reaction

Abstract

Woven covalent organic frameworks (woven COFs) represent a rare class of mechanically interlaced crystalline polymers whose synthesis is largely limited by the availability of suitable linkage chemistry. Herein, we report the first example of a vinylene-linked woven covalent organic framework, constructed through a Knoevenagel-type condensation between a Cu(I)-coordinated neocuproine node (Cu(DmPhen)2) and an extended aromatic dialdehyde linker under melt-polymerization conditions. The incorporation of a rigid copper-phenanthroline node and an elongated terphenyl-based aldehyde promotes framework interlocking, enabling the formation of a crystalline woven architecture featuring robust C═C linkages and permanent porosity. The resulting Cu-TPy COF exhibits a long-range periodicity, extended π-conjugation, and remarkable chemical stability. Owing to the synergistic combination of accessible copper centers and an ordered conjugated framework, Cu-TPy exhibits outstanding electrocatalytic activity for the oxygen reduction reaction (ORR) even in the absence of conductive additives, maintaining stable performance for more than 2 days of continuous operation. This work demonstrates the successful incorporation of vinylene linkages into the woven framework, thereby extending the conjugation pathway and broadening the structural diversity of woven porous materials.