Warp‐Weft Stack Strategy for Weaving 2D Porphyrin‐Based COFs from 1D Chains toward CO 2 Photoreduction

Abstract

ABSTRACT The development of efficient photocatalysts for converting carbon dioxide into valuable chemicals is crucial for sustainable energy. Porphyrin‐based covalent organic frameworks (COFs) represent a promising class of materials for photocatalytic CO 2 reduction. In this work, a novel synthetic strategy termed “warp‐weft stack” is presented and utilized to design and synthesize a series of 2D porphyrin‐based COFs from 1D chain precursors. The strategy employs low‐symmetry (C 2 ) porphyrin and dialdehyde monomers, which first form 1D chains via imine bonds and are then woven into 2D frameworks through axial metal coordination. Comprehensive characterization confirms that the cobalt‐porphyrin‐based COFs exhibit a partially ordered layered structure with moderate crystallinity, suggesting that the metal center plays a key role in directing the dimensional evolution from chains to sheets. In contrast, the metal‐free analog forms an amorphous aggregate. In a photocatalytic system with [Ru(bpy) 3 ]Cl 2 and ascorbic acid, the cobalt‐porphyrin COF demonstrates markedly enhanced activity and selectivity for CO 2 reduction. This study not only provides a novel pathway for the bottom‐up construction of dimensionally controlled porous materials but also underscores the importance of integrated metal sites in directing framework assembly and optimizing catalytic function for sustainable chemical synthesis.