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

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