Tetrahedral UMOFNs/Ag(3)PO(4) Core–Shell Photocatalysts for Enhanced Photocatalytic Activity under Visible Light

[Image: see text] A new visible-light-responsive tetrahedral ultrathin metal–organic framework nanosheet (UMOFNs)/Ag(3)PO(4) composite photocatalyst with a core–shell structure was readily synthesized by sonication in an organic solvent. Characterization methods for the photocatalyst included X-ray diffraction (XRD), scanning electron microscopy, transmission electron microscopy, and UV–vis diffuse reflectance spectroscopy. The XRD patterns of the composite photocatalyst before and after visible-light irradiation demonstrated that trace amounts of Ag ions in the composite photocatalyst easily transformed into Ag nanoparticles, which play a role in promoting charge separation at the interface of a heterojunction. The UMOFNs/Ag(3)PO(4) composite photocatalyst showed higher photocatalytic activity for the photodegradation of 2-chlorophenol (2-CP) under visible-light irradiation (>420 nm) than Ag(3)PO(4). The complete degradation of 2-CP was achieved in 7 min using the tetrahedral UMOFNs/Ag(3)PO(4) core–shell photocatalyst, and the apparent reaction rate was approximately 26 times higher than that of pure Ag(3)PO(4). Further, a scavenger experiment showed h(+) and O(2)(•–) were the major reactive species involved in the photocatalytic reaction system. This enhanced photocatalytic activity results from the efficient separation of photoinduced electron–hole pairs and the increase of interface area between Ag(3)PO(4), UMOFNs, and the Ag nanoparticles.