Improved Visible-Light-Induced Photocatalytic Performance of ZnAl Layered Double Hydroxide by Incorporation of Ni2.

NiZnAl layered double hydroxides (LDH) with Ni/Zn/Al ratios ranging from 0.1/2/1 to 1/2/1 were papered by coprecipitation. The prepared samples were characterized by multiple 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 incorporation of Ni2+ into the brucite sheets preserves the layered structure of ZnAl LDH. The doped Ni2+ serves as the photogenerated charges separator and improves the visible light photocatalytic activity of ZnAl LDH at a reasonable content. A degradation mechanism based on the hydroxyl radical as the active species was proposed.