Enhanced photocatalytic <scp> CO ₂ </scp> reduction of covalent triazine‐based photocatalyst: Mechanistic insights from time‐resolved spectroscopy

Abstract Photocatalytic conversion of waste carbon dioxide (CO 2 ) into fine chemicals is crucial for solar energy utilization and mitigating the global climate crisis. Artificial photocatalysis based on the integrated biocatalyst offers a promising approach for converting CO 2 into high‐value chemicals. The development of metal‐free heterogeneous photocatalysts has gained significant attention as a sustainable platform for practical artificial photocatalytic systems. In this study, we report a one‐pot synthesis of covalent triazine‐based photocatalysts (CTPs) and their photocatalytic applications. The as‐synthesized CTPs exhibit excellent photocatalytic performance, achieving the generation of HCOOH from CO 2 with a yield of 224.85 μM. The underlying photo‐physical properties of CTPs were investigated by using systematic time‐resolved laser spectroscopies. These measurements reveal that the formation of a long‐lived charge transfer state in CTPs at the late time window is strongly correlated with the enhanced photocatalytic efficiency by delaying the ultrafast charge recombination. This study will serve as a benchmark example of heterogeneous photocatalysts and their wide applications for CO 2 fixation and solar chemical production.