Synthesis of molybdenum trioxide/graphite carbon nitride heterojunction modified by biomass carbon dots and its application in photocatalytic degradation of methylene blue

Herein, a hexagonal molybdenum trioxide/graphite carbon nitride heterojunction modified by biomass carbon dots was synthesized by a simple one-pot method and successfully applied to the degradation of methylene blue as a photocatalyst. It was confirmed that under optimal compounding conditions, graphite carbon nitride and hexagonal molybdenum trioxide combined to form a heterojunction, and the coupling interface accelerated the charge transfer efficiency. The modification of supplementary biomass carbon dots can improve the photocatalytic activity of the photocatalyst for the degradation of methylene blue. The proposed heterojunction shows better photocatalytic activity than bulk graphite carbon nitride and has good reusability and stability. After irradiation with simulated visible light for 1 h, the degradation rate of methylene blue by the heterojunction reached 67 %, which was 2.7, 2.6 and 5.8 times higher than that of bulk graphite carbon nitride, pure hexagonal molybdenum trioxide and pure carbon dots, respectively.