Hydrothermal Synthesis of Iodine-Doped Bi2WO6 Nanoplates with Enhanced Visible and Ultraviolet-Induced Photocatalytic Activities

Abstract EN

The iodine-doped Bi2WO6 (I-BWO) photocatalyst was prepared via a hydrothermal method using potassium iodide as the source of iodine.

The samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM) and selected area electron diffraction (SAED), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy (DRS), and photoluminescence (PL) spectroscopy.

The photocatalytic activity of I-BWO for the degradation of rhodamine B (RhB) was higher than that of pure BWO and I2-BWO regardless of visible light (>420 nm) or ultraviolet light (<400 nm) irradiation.

The results of DRS analysis showed that the I-BWO and I2-BWO catalysts had narrower band gaps.

XPS analysis proved that the multivalent iodine species including I0 and I− were coadsorbed on the defect surface of Bi2WO6 in I-BWO.

The enhanced PL intensity revealed that a large number of defects of oxygen vacancies were formed by the doping of iodine.

The enhanced photocatalytic activity of I-BWO for degradation of RhB was caused by the synergetic effect of a small crystalline size, a narrow band gap, and plenty of oxygen vacancies.