Covalent Organic Frameworks for Photocatalytic CO ₂ Reduction: Metal Integration Principles, Strategies and Functions

ABSTRACT Covalent organic frameworks (COFs) have been recognized as versatile platforms for photocatalytic CO 2 reduction reactions (CO 2 PRR), owing to their inherent merits of tunable photo‐responsiveness, structural flexibility, high porosity and molecular precision. However, the adsorption and activation of CO 2 within pristine COFs remain challenging due to the lack of strong binding and catalytic sites. To address this, extensive efforts have been dedicated to incorporating active metal centers into COFs, to enhance charge separation, CO 2 adsorption, and redox processes. Despite these advances, a comprehensive analysis correlating metal incorporated strategies with photocatalytic performance remains lacking. This review timely fills this gap by linking the structural and functional properties of metal‐embedded COF with CO 2 PRR activities. We first outline the structural features and design principles of COFs, then highlight representative metal incorporation approaches and the resulting structure–function relationships. Finally, perspectives are presented on the opportunities and challenges of advancing metal‐modified COFs for solar‐driven CO 2 conversion with high performance and on‐demand selectivity. This review will also offer critical insights into intelligent COFs design and inspire future developments in photocatalytic carbon dioxide capture and upgrading.