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

Abstract

The Cs3PW12O40/Ag3PO4 (CsPW/Ag3PO4) heterojunction photocatalyst in this study was prepared using a simple chemical precipitation method. Spherical CsPW particles were successfully deposited on Ag3PO4 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/Ag3PO4 heterojunction photocatalyst can effectively degrade RhB. The Z-scheme 3% CsPW/Ag3PO4 heterojunction photocatalyst has a higher photocatalytic ability compared with the single-component photocatalyst CsPW or Ag3PO4. 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/Ag3PO4 heterojunction photocatalyst. The reactive species trapping experiments demonstrated photogenerated holes (h+) and superoxide radicals (•O2-) to be the main active components of photocatalytic degradation. A possible photocatalytic mechanism is subsequently proposed.