Photocatalytic degradation mechanism of phenanthrene over visible light driven plasmonic Ag/Ag 3 PO 4 /g-C 3 N 4 heterojunction nanocomposite

Visible light driven plasmonic Ag/Ag PO /g-C N heterojunction nanocomposite with regular morphology was prepared via a modified facile method. The two-dimensional ultrathin g-C N nanosheet is uniformly wrapped on the surface of Ag PO nanopolyhedron. A charge transfer bridge was built between Ag PO nanopolyhedron and g-C N nanosheet due to the reduction of Ag nanoparticles. This structure can inhibit the recombination of photogenerated electron-hole pairs and promote the transfer of photogenerated carriers, so as to produce more active species for participating in the photocatalytic reaction. In addition, the surface plasmon resonance (SPR) of appropriate Ag nanoparticles enhanced the absorption and utilization of visible light. Compared with Ag PO and Ag/Ag PO , Ag/Ag PO /g-C N showed higher photocatalytic activity. Under visible light irradiation, the degradation rate of phenanthrene (PHE) was 0.01756 min , which was 3.14 times and 2.38 times that of Ag PO and Ag/Ag PO , respectively. After four cycles of photocatalytic reaction, the Ag/Ag PO /g-C N photocatalyst still maintained high photocatalytic activity. The active sites of PHE were predicted by Gaussian simulation calculation and combined with intermediate products identification of GC-MS, the possible degradation pathway of PHE was speculated. This research has reference significance for the construction of plasmonic heterojunction photocatalyst in the field of environmental pollution remediation.