Facile synthesis of Zn(II)-doped g-C3N4 and their enhanced photocatalytic activity under visible light irradiation

Zn(II)-doped graphitic carbon nitride (g-C3N4) with high photodegradation activity was prepared by one facile step. The morphology and structure of the prepared Zn(II)-doped g-C3N4 were investigated, and the results showed that Zn(II) could self-disperse during the pyrolysis process and Zn–N bond was formed between g-C3N4 and Zn. The dope of Zn(II) influenced the structure of g-C3N4. The performance of photocatalytic activity of Zn(II)-doped g-C3N4 series indicated that the doped g-C3N4 with a small quantity of Zn (0.10 wt%) exhibits the best photocatalytic performance. The photodegradation activity for methyl orange was 2 times higher than that of pure g-C3N4. However, the photocatalytic activity decreased with the further increased content of Zn, which may be attributed to the structure change of g-C3N4 and the interaction of Zn–N bond between Zn and g-C3N4. Moreover, Zn(II)-doped g-C3N4 showed good recycling photocatalytic stability.