Construction of S-Type PDI/BiOBr Heterojunctions and Their Photocatalytic Activity

Constructing an S-type heterojunction to promote photogenerated carrier separation is a valid method to ameliorate this problem. In this work, self-assembled perylenetetracarboxylic diimide (PDI) was modified on the surface of two-dimensional (2D) BiOBr nanosheets using a continuous ion layer adsorption method. To explore its microstructure, photoelectric properties, and other characteristics, the electron transport channel constructed between self-assembled PDI and BiOBr hinders photogenerated electron-hole recombination. Under visible light irradiation, when the rhodamine B (RhB) was 50 mg/L, the removal rate over 1/3 PDI/BiOBr reached 98% in 60 min, and the rate constant was 15.9 times that over self-assembled PDI and 13 times that over BiOBr. In degrading methyl orange (MO), the removal rate over 1/3 PDI/BiOBr was 65.8% in 60 min, and the rate constant was 5.7 times that over self-assembled PDI and 3.4 times over BiOBr. After the ESR test, O2− is proved to be the main active species in the reaction.