Degradation of Rhodamine B Under Visible-Light by Cu-Doped ZnAl Layered Double Hydroxide.

The Cu-doped ZnAl layered double hydroxides (LDH) were papered by coprecipitation. The prepared samples were characterized by mutiple techniques including X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) surface area, scanning electronic microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and UV-vis diffuse-reflectance spectroscopy (UV-vis DRS). The doping of Cu into the LDH sheets results in formation of the distorted CuO6 octahedrons which contribute for the excitation of electrons under visible light. The doped Cu also serves as photo-generated charges separator and improves the visible-light-driven photocatalytic activity of ZnAl LDH. A degradation mechanism based on the hydroxyl radical as the active species was proposed.