Novel preparation of stable and highly photocatalytic Z-scheme Cs3PW12O40/Ag3PO4 photocatalysts for the photocatalytic degradation of organic contaminants in water

The Cs 3 PW 12 O 40 /Ag 3 PO 4 (CsPW/Ag 3 PO 4 ) heterojunction photocatalyst in this study was prepared using a simple chemical precipitation method. Spherical CsPW particles were successfully deposited on Ag 3 PO 4 nanocrystals, all the as-prepared samples are characterized by X-ray diffraction pattern (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), UV visible spectroscopy (UV-Vis), and X-ray photoelectron spectroscopy (XPS). The catalyst activity in relation to rhodamine B (RhB) degradation was evaluated under visible light ( λ > 420 nm). The CsPW/Ag 3 PO 4 heterojunction photocatalyst can effectively degrade RhB. The Z-scheme 3% CsPW/Ag 3 PO 4 heterojunction photocatalyst has a higher photocatalytic ability compared with the single-component photocatalyst CsPW or Ag 3 PO 4 . The comparatively high photocatalytic performance can be attributed to the high matching of the energy band position and close interface contact, suggesting an enhanced separation efficiency of the photoinduced carriers of the CsPW/Ag 3 PO 4 heterojunction photocatalyst. The reactive species trapping experiments demonstrated photogenerated holes (h + ) and superoxide radicals to be the main active components of photocatalytic degradation. A possible photocatalytic mechanism is subsequently proposed. A Z-scheme heterojunction photocatalyst CsPW/Ag 3 PO 4 has been synthesized and it possesses excellent stability. The CsPW/Ag 3 PO 4 photocatalysts exhibited apparent visible-light absorption and weakened recombination of photogenerated electron/hole pairs. A possible photocatalytic reaction mechanism has been proposed.