Photocatalytic degradation of dinotefuran by layered phosphorus-doped carbon nitride and its mechanism

Abstract It is well known that the widespread residue of the neonicotinoids dinotefuran in aquatic environment has adverse effects on non-target organisms. Therefore, the efficient removal of dinotefuran in water environment is an important measure to control its safety risk. In the present study, layered phosphorus-doped carbon nitride (HPCN0.5) was prepared via a simple hydrothermal method and applied for photocatalytic degradation of dinotefuran. With the addition of phosphorous acid, a tube-like structure was observed in HPCN0.5 and planar sheets were stacked inside the tubes. Compared to bulk g-C3N4, the degradation efficiency of dinotefuran was 6 times higher. According to the reaction mechanism and product identification analysis, the main photodegradation pathways correspond to demethylation and hydroxylation. The result of the acute toxicity test revealed the toxicity of dinotefuran to earthworm was greatly reduced after photodegradation by HPCN0.5. In addition, HPCN0.5 was capable of simultaneously removing three other commonly used neonicotinoids. This work proved that HPCN0.5 has great potential to be applied in alleviating negative effects of neonicotinoids on the non-target organisms and environment.