LAUSR

Abstract In view of the deterioration of the environment and the shortage of resources, it is necessary to develop efficient photocatalysts for the degradation of organic pollutants. Herein, a novel and environmentally friendly ZnNb2O6/g-C3N4 heterojunction nanocomposite was synthesized by calcination-hydrothermal method successfully. The chemical and physical capabilities of the material were characterized by various kinds of analytical instruments. Compared with ZnNb2O6 and g-C3N4, ZnNb2O6/g-C3N4 showed the strongest photocatalytic activity. The nanomaterial was used in the removal of the pollutant 2,4-DCP. The effects of degradation conditions were discussed including component ratio, material dosage, initial analyte concentration, pH and salinity. After 180 minutes’ simulated sunlight illumination, the removal efficiency of 2,4-DCP (10 mg/L) reached 95.7% under the optimum condition. Furthermore, the possible photocatalytic mechanisms were discussed according to four aspects: (i) The conformation of the active species; (ii) The calculation of valence and conduction band; (iii) The analysis Z-scheme heterojunction mechanism; (iv) The speculation of feasible photocatalytic paths. In conclusion, the ZnNb2O6/g-C3N4 (ZC-7) nanocomposite has the least recombination rate of electron-hole pairs and the highest photocatalytic efficiency.