Photocatalytic uranium conversion in an air atmosphere is closely related to the generation of reactive oxygen species (ROS), including H 2 O 2 and .O 2 − . Highly effective visible light‐driven uranium extraction without sacrificial agents is highly demanded but limited by inefficient photocarrier separation/transportation and ROS production. Herein, a facile acceptor regulation strategy was developed to fabricate two benzotrithiophene‐based covalent organic frameworks (BTT‐DAB and BTT‐BD) with modulated π skeletons. The introduction of aromatic amines ligands DAB with a lower torsion angel not only improves the structural planarity but also decreases the distance between BTT donors. BTT‐DAB shows optimized visible light harvesting capability and accelerated charge dissociation/transfer owing to the planar and continuous π ‐electron delocalization channels. BTT‐DAB exhibits high uranium extraction efficiency, excellent selectivity and reusability under visible light. The in situ generated H 2 O 2 is promoted in BTT‐DAB through a two step 1 e −1 oxygen reduction reaction, which facilitates the precipitation of uranium as metastudtite. This work highlights a facile but general structural regulation strategy to enhance the photocatalytic uranium extraction performance.
Han et al. (Fri,) studied this question.