Preparation of La-doped Bi2WO6 with rich oxygen vacancies and enhanced photocatalytic performance for removal of Rhodamine B

To ameliorate the photocatalytic performance of Bi2WO6, La-doped Bi2WO6 photocatalysts were prepared by a hydrothermal method using glacial acetic acid as solvent. The samples were carefully characterized by serval analytic methods. X ray photoelectron spectroscopy (XPS) and low-temperature electron spin-resonance (ESR) spectroscopy demonstrate that La-doped Bi2WO6 photocatalysts have rich oxygen vacancies (OVs). Elemental mapping and XPS confirm the existence of La in Bi2WO6. Doping La into Bi2WO6 significantly boosts the level of OVs, separation of photoinduced carriers and the generation of superoxide radical (center dot O2-). Photocatalytic perfor-mance of the samples was evaluated by removal of Rhodamine B (RhB) under simulated sunlight irradiation. The results indicate that the activity of La-Bi2WO6 is higher than the reference Bi2WO6. When the content of La is 0.6%, the degradation rate constant of RhB on the 0.6% La-Bi2WO6 is 1.83 times of that of the blank Bi2WO6. Doping La into Bi2WO6 is a reliable approach to promote the photocatalytic activity of Bi2WO6.

Automated summary

To improve the photocatalytic performance of Bi2WO6, La-doped Bi2WO6 photocatalysts were prepared and characterized. The results showed that La doping increased the level of oxygen vacancies in Bi2WO6 and enhanced the separation of photoinduced carriers and the generation of superoxide radicals. Under simulated sunlight irradiation, La-Bi2WO6 exhibited higher photocatalytic activity compared to pure Bi2WO6.