One-Pot Polyvinyl Alcohol- Assisted Hydrothermal Synthesis of Hierarchical Flower-Like BiOCl Nanoplates with Enhancement of Photocatalytic Activity for Degradation of Rhodamine B

摘要

We have successfully synthesized hierarchical flower-like bismuth oxychloride nanoplates by a polyvinyl alcohol-assisted hydrothermal process. The as-synthesized products were characterized by a collection of techniques, such as X-ray diffraction, scanning electron microscopy, UV-Vis diffuse reflectance spectroscopy, and N-2 adsorption-desorption isotherms. The concentration of polyvinyl alcohol and hydrothermal time were vital effects for formation of hierarchical flower-like bismuth oxychloride nanostructures. Rhodamine B (RhB) was selected to evaluate the photocatalytic performance of as-synthesized samples under visible light irradiation. The degradation was undergone through a photosensitization pathway. The hierarchical flower-like bismuth oxychloride nanoplates showed much higher RhB removal efficiency than other bismuth oxychloride samples and commercial Degussa TiO2. The active species trapping experiments revealed that the superoxide radicals (O-center dot(2)-) were the main active species in aqueous solution. In combining with the N-2 bubbling experiment, photocatalysis mechanism was finally proposed.