Three-Dimensional Porphyrin and Phthalocyanine-Based Covalent Organic Frameworks for Boosting Urea Oxidation

Porphyrin and phthalocyanine-based covalent organic frameworks (COFs) have emerged as versatile scaffolds for developing high-performance photo- and electrocatalysts. By enabling precise anchoring of metal species onto their cores, these COFs allow for meticulous tuning of chemical and electronic properties, facilitating single-atom distribution and achieving outstanding catalytic performance. However, the majority of these COFs are restricted to two-dimensional (2D) architectures, where the catalytic activity of the metal centers is often compromised due to eclipsed stacking layers, limiting their optimization potential. To address this challenge, we report the synthesis of three-dimensional (3D) porphyrin and phthalocyanine-based COFs with a cyt topology. This innovative structural arrangement facilitates the atomic-level distribution of distinct metal species across steric exposed networks, and the synergistic effect of bimetallic sites leads to exceptional electrocatalytic activity in urea oxidation reactions with a current density of 10 mA cm^-2 at just 1.37 V_RHE. This study not only broadens the topological diversity of 3D COFs but also establishes a platform for achieving uniform and accessible multimetal distributions, paving the way for synergistic electrocatalytic materials.