Facile synthesis of Ni-doping Bi₂WO₆ nano-sheets with enhanced adsorptive and visible-light photocatalytic performances

Bi₂WO₆ nano-sheets doped with various amounts of nickel (Ni) were prepared by hydrothermal method, and their microstructure and photocatalytic performance for degrading rhodamine B (RhB) and ciprofloxacin (CIP) under simulated solar light irradiation were investigated. The effective incorporation of Ni atoms in Bi₂WO₆ was confirmed by energy-dispersive spectroscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and Raman spectroscopy. Ni-doping decreased the crystallite size of Bi₂WO₆ and improved its specific surface area and surface electrical property. Furthermore, Ni atoms acting as electron traps facilitated the separation of photo electron–hole pairs. Accordingly, both adsorptive and photocatalytic performances of the Ni–Bi₂WO₆ were improved compared to undoping Bi₂WO₆. The 0.15-Ni–Bi₂WO₆ (Ni/W, molar ratio) displayed the best adsorptive and photocatalytic activities among the Bi₂WO₆ samples doped with various elements. The photogenerated holes were the predominant reactive species responsible for the photodegradation of RhB by 0.15-Ni–Bi₂WO₆. Solution pH could influence the adsorptive and photocatalytic performances of 0.15-Ni–Bi₂WO₆ with the best performances under acidic condition. Copyright © 2018 Springer Science+Business Media, LLC.