Hydrothermal synthesis of Sm-doped BiWO flower-like microspheres for photocatalytic degradation of rhodamine B

• Published in: CrystEngComm Vol. 21; no. 41; pp. 628 - 6218
• Main Authors: Zhang, Xianghui, Zhang, Mingming, Cao, Kaixuan
• Format: Journal Article
• Published: 21.10.2019
• ISSN: 1466-8033
• DOI: 10.1039/c9ce01043b

In this paper, a series of Sm-doped Bi 2 WO 6 samples with different Sm contents ( x Sm-BWO, x = 0.0%, 0.5%, 1.0%, and 2.0%) were successfully synthesized by the hydrothermal method and well characterized by X-ray diffraction (XRD), UV-vis diffuse reflectance spectroscopy (UV-vis DRS), scanning electron microscopy (SEM), photoluminescence (PL) spectroscopy, X-ray photoelectron spectroscopy (XPS), and N 2 adsorption-desorption tests. The XRD results indicated that the Sm-doped Bi 2 WO 6 samples exhibited an orthorhombic crystal structure and Sm 3+ replacing Bi 3+ entered into the Bi 2 WO 6 lattice, producing slight reduction in the average crystallite size. The UV-vis DRS results indicated that Sm 3+ doping significantly narrowed the energy band gap. The SEM images show that Sm-doped Bi 2 WO 6 has 3D flower-like microspheres constructed by many loosely connected nanosheets. The photocatalytic activities of the as-prepared samples were evaluated by using rhodamine B (RhB) as the target organic pollutant. It was found that 0.5% Sm-Bi 2 WO 6 has the highest photocatalytic property with a 98.4% removal rate of RhB within 30 min, which was ascribed to the optimum optical absorption activity and the larger specific surface area. It also showed superior stability and reusability after four recycling experiments. Finally, the possible mechanism of photocatalytic degradation was discussed according to the energy band structure and the radical-trapping experiments. Sm-doped Bi 2 WO 6 with 3D flower-like microspheres structure shows extremely high photodegradation activity and superior stability and reusability because of the optimum optical absorption activity and the larger specific surface area.