Preparation and Visible Light Catalytic Performance of Fe3O4/Ag/BiVO4/Sepiolite Composites

Graphical A range of Fe 3 O 4 /Ag/BiVO 4 /sepiolite composite materials, featuring varying Fe 3 O 4 concentrations, were synthesized utilizing the co-precipitation method. The inherent magnetic characteristics of Fe 3 O 4 , combined with the resultant Z-type heterojunction structure, confer exceptional photo-catalytic prowess upon the material. This enables swift degradation of rhodamine B, and furthermore, facilitates its retrieval for subsequent reuse. To increase specific surface area and light utilization of photo-catalysts, a series of Fe 3 O 4 /Ag/BiVO 4 /sepiolite composites with different Fe 3 O 4 contents were synthesized via co-precipitation. The structure, composition, and optical properties of these composites were characterized using X-ray diffraction (XRD), nitrogen adsorption and desorption (BET), UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS), and fluorescence spectroscopy (PL). The photo-catalytic activity of the composites was further evaluated using rhodamine B as a model for photo-catalytic degradation. The results revealed that the composites with optimal Fe 3 O 4 loading exhibited the narrowest bandgap width, approximately 2.13 eV, and the highest electron-hole pair separation efficiency. Rhodamine B could be almost completely degraded within a short illumination time in the presence of the Fe 3 O 4 /Ag/BiVO 4 /sepiolite composites. The degradation mechanism of rhodamine B was proposed to involve the improvement of the photo-catalytic activity of the resulting composites by the Fe 3 O 4 and the Z-type heterojunction structure. Additionally, the composites could be recycled and reused multiple times, making them an environmentally friendly and sustainable option.