On the heterostructured photocatalysts Ag3VO4/g-C3N4 with enhanced visible light photocatalytic activity

Heterostructured photocatalysts Ag3VO4/g-C3N4 were prepared by deposition-precipitation method in order to anchor Ag3VO4 on the surface of N-vacancy g-C3N4 (g-C3N4-VN). The photocatalytic activity of the samples was evaluated by degrading rhodamine B (RhB) in aqueous solution. Compared with the pure Ag3VO4 and g-C3N4-VN, the heterojuncted photocatalyst 65 wt% Ag3VO4/g-C3N4-VN exhibits the best activity under visible light irradiation. The photodegradation rate constant of 65 wt% Ag3VO4/g-C3N4-VN is 0.0556 min−1, which is 23.4, 5.8 and 6.4 times of that of pure Ag3VO4, pure g-C3N4-VN and P25, respectively. The excellent photocatalytic performance of the Ag3VO4/g-C3N4-VN catalysts can be ascribed to the matched band structures of Ag3VO4 and g-C3N4, which strengthened the formation of the heterojuncted photocatalyst. The unique heterostructured photocatalyst is favorable for retarding the recombination of photogenerated electrons and holes, thus the photocatalytic activity is significantly increased. Further experiment also reveals that the •O2− and h+ are the major active species in the degradation of RhB.