Synergistic Modulation of the Separation of Photo‐Generated Carriers via Engineering of Dual Atomic Sites for Promoting Photocatalytic Performance

Abstract The separation efficiency of photo‐generated carriers is still a great challenge that restricts the practical application of photocatalytic technology. The design of spatial separation path for photo‐generated carriers at atomic level provides an innovative approach to address this challenge. Herein, a facile dual atomic sites strategy, consisting of Cu‐N 4 and C‐S‐C active moieties decorated on polymeric carbon nitride (Cu SAs/p‐CNS) is reported to simultaneously achieve the highly efficient separation of photo‐generated electrons and holes for boosting photocatalytic performance. As a proof of concept, the Cu SAs/p‐CNS is successfully applied to the photo‐oxidation of 5‐hydroxymethylfurfural (HMF) to 2,5‐diformylfuran (DFF), which exhibits 77.1% HMF conversion and 85.6% DFF selectivity under visible light irradiation. The activity is considerably higher than that of bulk p‐CN, S doped p‐CN, and p‐CN supported Cu single atom catalysts. Theoretical calculations and experimental results suggest that, during photocatalytic reaction, the isolated Cu‐N 4 sites directly capture photo‐generated electrons, while the surrounding S atoms bear photo‐generated holes, which synergistically facilitates the separation of photo‐generated carriers and thus results in enhanced photocatalytic activity. This study provides a new perspective for the rational design of high performance photocatalysts at atomic level.