New insight into the enhanced visible light-driven photocatalytic activity of Pd/PdCl2-doped Bi2WO6 photocatalysts

A bismuth-based compound, Bi2WO6, was successfully synthesized using a facile hydrothermal method. Aiming to improve its photocatalytic activity under visible light irradiation, Pd/PdCl2 was first doped onto the surface of Bi2WO6 via a photo-reduction method. The prepared Pd/PdCl2-Bi2WO6 samples were characterized based on crystal structures, chemical states, atomic compositions, and morphologies as well as photoabsorption properties. In the screening tests for photocatalytic activity, the 4% Pd-Bi2WO6 sample performed with the highest removal efficiency with respect to the degradation of phenol in wastewater. This sample exhibited better in complete degradation of phenol under visible light irradiation, compared to TiO2 under ultraviolet irradiation. A possible mechanism for the enhanced visible light-driven photo catalytic activity by means of loading Bi2WO6 with Pd was also suggested. This work sheds light on the potential applications of noble metal nanoparticles in visible light-driven photocatalysis. (C) 2017 Elsevier Inc. All rights reserved.