Low-temperature plasma-induced porous Sb₂WO₆ microspheres with rich oxygen vacancies to promote high-performance photocatalytic activity

The escalating issue of water pollution has sparked significant attention among researchers in the field of photocatalysis. Consequently, it holds immense significance to develop photocatalysts that exhibit high charge separation efficiency and stability for effectively degrading pollutants in water. In this study, OV-Sb₂WO₆-X photocatalyst was synthesized by incorporating oxygen vacancies into pristine Sb₂WO₆. The introduction of oxygen vacancies significantly enhanced the charge separation efficiency, resulting in a substantial improvement in the photocatalytic activity. The content of oxygen vacancies was controlled by plasma treatment time, processed for 10, 20 and 30 min, and electron paramagnetic resonance (EPR) test demonstrated the introduction of oxygen vacancies successfully. Furthermore, X-ray photoelectron spectroscopy (XPS) characterized the internal electron flow direction of the photocatalyst. OV-Sb₂WO₆-20 showed the degradation rate of Rhodamine B (RhB) that nine times of the Sb₂WO₆, while the Tetracyclines (TC) degradation rate showed 3.5 times that of Sb₂WO₆. Moreover, OV-Sb₂WO₆-20 exhibited superior stability in terms of recycling activity and material structural integrity. Additionally, free radical trapping experiments and electron spin-resonance spectroscopy characterization demonstrated that h⁺ played a crucial role as the reactive species during the degradation process. This research presents a viable approach for the modification of Sb₂WO₆-based materials, enabling effective treatment of dye wastewater and achieving successful purification. © 2023 Elsevier B.V.