Novel Yb3+/Nd3+ Co-Doped Bismuth Tungstate For Excellent Photocatalytic Performance: Construction And Synergistic Effect Of Oxygen Vacancies And In-Built Yb3+/Yb2+ Redox Center

A novel Yb3+/Nd3+-Bi2WO6 photocatalyst with oxygen vacancies was synthesized through one-step hy-drothermal method. The 1.5%Yb3+/0.5%Nd3+-Bi2WO6 exhibited an outstanding performance, whose de -composition efficiency of Rhodamine B was 3.7 times higher than that of bare Bi2WO6. The crystal structure, morphology, chemical state and optical properties were systematically investigated to reveal the me-chanism of its enhanced photocatalytic performance. Its excellent visible light absorption and an absorption peak at 584 nm due to the excitation of Nd3+ were confirmed by the UV-Vis diffuse reflectance spectra of composite samples. Meanwhile, not only the existence of dopants was confirmed by the X-ray spectroscopy, but the in-built Yb3+/Yb2+ redox center was also revealed. Moreover, the formation of oxygen vacancies and Yb3+/Yb2+ redox center could effectually restrict the recombination of photo-generated electron-hole pairs, which could be demonstrated by photoluminescence characterization. Consequently, the mechanism of an enhanced photocatalytic performance was speculated about the extension range of visible light and the synergistic effect of oxygen vacancies as well as the redox center. This study provides a new concept, a rational design and the acquirement of a high-efficiency visible-light-driven photocatalyst. (C) 2021 Elsevier B.V. All rights reserved.