Hydrothermal Synthesis and Characterization of Ce³⁺ Doped Bi₂MoO₆ for Water Treatment

Abstract

Rhodamine B (RhB) and tetracycline (TC) are the typical organic pollutants in wastewater. More and more attentions have been paid to the removal of them. In the present work, pure and various contents of Ce³⁺ doped Bi₂MoO₆ nanostructures were synthesized by a facile hydrothermal method. They were characterized by X-ray diffraction (XRD), UV–Vis diffuse reflectance spectra (UV–Vis DRS), Raman spectra, photoluminescence spectra, scanning electron microscopy (SEM), N₂ adsorption–desorption tests and X-ray photoelectron spectra. XRD patterns show that the pure and Ce³⁺ doped Bi₂MoO₆ exhibit orthorhombic crystal structure and Ce³⁺ is successfully doped into Bi₂MoO₆ lattice. UV–Vis DRS results indicate that a narrower band gap was obtained after Ce³⁺ doped into Bi₂MoO₆. SEM images show that the Ce-doped Bi₂MoO₆ is 3D microspheres constructed by many nanosheets. The photocatalytic activities of the as-prepared samples were evaluated by the degradation of RhB and TC. The 0.5% Ce³⁺ doped Bi₂MoO₆ exhibits the best photocatalytic activity of 96.6% within 20 min for RhB removal and 78.2% within 90 min for TC removal, respectively. The improved photocatalytic activity can be ascribed to the low recombination and easy migration of photogenerated electron hole pairs derived from the better crystallinity, optimum optical absorption activity and morphology of microspheres after Ce³⁺ doping. In addition, it also had a good stability and reusability after ten times of recycling experiments.

Graphic Abstract