Enhanced Photocatalytic Activity by Silver-Modified Bismuth Vanadate

摘要

Silver-modified bismuth vanadate (Ag-BiVO_4)) photocatalysts were easily prepared via the co-precipitation method. The effects of silver contents on the chemical properties of BiVO_4 were evaluated. The prepared Ag-BiVO_4 samples were characterized by several techniques such as X-ray diffractometry (XRD), scanning electron microscopy (SEM), and diffused reflectance UV-Vis spectroscopy (DRS). The mixed phase of monoclinic scheetlite structure and characteristic peaks of silver particles were found. Silver contents strongly affect the morphology of the prepared Ag-BiVO_4 samples. DRS spectra revealed that the synthesized Ag-BiVO_4 samples exhibited strong absorption in the visible region. The absorption in the visible zone is responsible for the high photocatalytic activity of Ag-BiVO_4 under visible light irradiation. The photocatalytic degradation of methylene blue under visible light irradiation was studied using the BiVO_4 as photocatalysts. The photocatalytic results reveal that the prepared Ag-BiVCO_4 samples could degrade the methylene blue dye.