Synthesis and photocatalytic application of trinary structural g-C3N4/Ag/Ag3PO4 composite nanomaterials

Trinary g-C 3 N 4 /Ag/Ag 3 PO 4 heterostructures with different Ag content were designed and synthesized by in situ deposition and reduction routes. The photocatalytic performances of these heterostructures were investigated under visible light (λ   >   450   nm) and simulated sunlight. Moreover, the influence of Ag content and ratio of each component on the photocatalytic performance of g-C 3 N 4 /Ag/Ag 3 PO 4 was also studied. As a result, the photocatalytic activities of all these g-C 3 N 4 /Ag/Ag 3 PO 4 samples were higher than commercial P25 (TiO 2 ). Moreover, sample S1 (the ratio of g-C 3 N 4 , Ag 3 PO 4 and Ag is 1: 2.52: 0.12) showed the better photocatalytic activities than other g-C 3 N 4 /Ag/Ag 3 PO 4 samples (S2 and S3) and g-C 3 N 4 /Ag 3 PO 4 (1: 3) under the same light irradiation. It indicated that small amount of Ag nanoparticles could improve the photocatalytic performances by compared with g-C 3 N 4 /Ag 3 PO 4 sample. And S1 showed a stable photodegradation after 6 times of cycle experiments under simulated sunlight. The stable and significant superior photocatalytic performance of g-C 3 N 4 /Ag/Ag 3 PO 4 could be attributed to the fast charge separation among g-C 3 N 4 , Ag and Ag 3 PO 4 during the Z -scheme charge transfer and recombination process.