Unveiling Triazine Functionality in COF‐Molecular Hybrids for Efficient CO <sub>2</sub> Photoconversion
Ying He, L. Zheng, Wantian Mei, Jianjun Zhang, Chuanbiao Bie, Jiaguo Yu, Hermenegildo Garcı́a, Feiyan Xu
Abstract
Abstract Photocatalytic CO 2 conversion offers a sustainable route for solar fuel production but is hindered by weak CO 2 adsorption, inefficient charge separation, and inadequate stabilization of key intermediates. Covalent organic frameworks (COFs) provide a modular platform, yet the structure‐function relationships that govern their photocatalytic performance remain insufficiently understood. Here, a triazine‐imine COF (TPT‐COF) integrated with Co(II) bipyridine complexes (Cobpy) is developed to elucidate the functional role of triazine moieties in facilitating efficient CO 2 ‐to‐CO conversion. Comparative analysis with a triazine‐free analog (TPB‐COF) reveals that triazine incorporation enhances Lewis basicity and CO 2 chemisorption, while simultaneously inducing a distinct Co─N 5 Cl coordination environment that promotes dual‐channel charge transport and interfacial electron injection. In situ and time‐resolved spectroscopic studies, together with density functional theory calculations, consistently demonstrate that the triazine framework stabilizes the *COOH intermediate by lowering the reaction barrier. As a result, Cobpy‐TPT‐COF achieves a CO evolution rate of ≈1.3 mmol g −1 , exceeding its imine‐based counterpart by over an order of magnitude. These findings provide mechanistic insight into COF‐molecular hybrid systems and establish guiding principles for the rational design of next‐generation photocatalysts for solar‐driven CO 2 reduction.