Layered double hydroxides as heterostructure LDH@Bi2WO6 oriented toward visible-light-driven applications: synthesis, characterization, and its photocatalytic properties

In this work, we report the obtention of the LDH@Bi(2)WO(6)heterostructure using an easy and low-cost method. The LDH was synthesized through the co-precipitation method with the metallic ratio of Mg2+/Al3+= 2.0, while the bismuth tungstate nanoplates were prepared using the hydrothermal method. The LDH@Bi(2)WO(6)heterostructure was obtained mixing LDH in water with 20 wt% of Bi2WO6. The LDH, Bi(2)WO(6)and LDH@Bi(2)WO(6)heterostructure were characterized by XRD, FTIR, N(2)sorption, SEM, TEM, Raman, and DRS. The photocatalytic activity of these materials was evaluated by the photodegradation of RhB in aqueous solution under simulated sunlight irradiation. The characterization revealed the deposition of LDH on the surface of Bi2WO6, as well as a considerable increase in the photocatalytic activity (synergistic effect) of the LDH@Bi(2)WO(6)heterostructure when compared with pure LDH and Bi2WO6. For this material, the degradation rate, velocity constant rate, and half-life time experimentally obtained were equal to 98.7%, 51.9 x 10(-3) min(-1), and 13.3 min, at the end of 75 min in the photodegradation of RhB. It is also 166 times faster than the photolysis test, with a high stability after five consecutive photocatalytic cycles. Therefore, the LDH@Bi(2)WO(6)heterostructure is a promising material in the photodegradation of organic pollutants using visible-light as the source of radiation.