[Preparation of Ag-AgI/CN/MA Composites and Their Visible-light Photocatalytic Performance].

Ag-AgI/CN/MA photocatalysts were prepared by coupling graphitic carbon nitride (CN) with AgI/-AlO(AgI/MA) through a thermal polymerization method and Ag nanoparticles were deposited by photoreduction. The catalysts were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM), UV-vis diffuse reflectance spectra (UV-vis DRS), and transmission electron microscopy (TEM). The photocatalytic performance of different catalysts was evaluated under visible light irradiation (>420 nm). The effects of different conditions such as pH and catalyst dosage on photoreactions were also investigated. The results showed that Ag and Ag coexisted on the surface of the catalyst and Ag and AgI nanoparticles were uniformly distributed on the surface of CN. Compared with CN and Ag-AgI/MA, Ag-AgI/CN/MA composites exhibited better visible-light photocatalytic activity and stability, and the release of silver ions was significantly suppressed. At the catalyst dosage of 1 g·L and pH=7, Ag-AgI/CN/MA-2 exhibited the optimal photocatalytic performance. Ag-AgI/CN/MA-2 also showed high photoactivity for the degradation of dyes with different charges, such as rhodamine B (RhB), methyl red (MR) and congo red (CR).