Disorder–order structure of a-CeO2/SnFe2O4 heterojunction with enhanced exciton dissociation for the NIR-driven photocatalysis

Strong Coulomb force between photogenerated electrons and holes often results in high level exciton pairs during the photocatalytic process, which hinders the formation of reactive oxygen species (ROS) in the photocatalytic reaction, particularly for the photocatalysis under near infrared (NIR) irradiation. Hence, it is crucial to dissociate excitons into free carriers. In this study, we propose a novel amorphous–crystalline heterojunction of a-CeO 2 /SnFe 2 O 4 for the NIR-driven photocatalytic degradation and sterilization. The introduction of disorder–order interface in heterojunction could greatly enhance the built-in electric field, thereby serving for exciton dissociation. Additionally, the presence of oxygen vacant sites in the a-CeO 2 /SnFe 2 O 4 system can effectively modulate the electronic structure of the material, facilitating exciton dissociation in conjunction with the built-in electric field. The DFT simulation proved the positive impact of the disorder–order interface on charge separation, as well as its enhancement on the activation of O 2 and H 2 O molecules. This work provides a theoretical support for the creation of disorder–order interface to promote exciton dissociation and enhance photocatalytic performance.