Zn-Al layered double hydroxide-based nanocomposite functionalized with an octahedral molybdenum cluster exhibiting prominent photoactive and oxidation properties

A new layered double hydroxide (LDH)-based nanocomposite functionalized with an octahedral molybdenum atom cluster (MC) exhibiting prominent photoactive and oxidation properties was synthesized. Zn-Al LDH and Zn-Al LDH intercalated dodecyl sulfate compounds (abbreviated as LDH-1 and LDH-2 respectively) were prepared by the co-precipitation method in an aqueous solution. The MCs were simply introduced into the LDH-2 by an anion exchangeable method in dimethylformamide under ambient conditions. The extension of the basal spacing of the LDH-1 from 0.9 nm to about 5 nm by intercalating dodecyl sulfate and Mo-6 cluster was confirmed by several complementary technics. The octahedral structure of the Mo-6 cluster was retained on the outer surface between big nanosheets (NSs) and inner surface between the single layers that were confirmed by ultraviolet-visible absorption and photoluminescence experiments. The possible chemical bonding between the [(Mo6Cl8Cl6-x-ya)-Cl-i(H2O)(x)(a)(OH)(y)(a)](x-2) (x = 0, 1 or 2 and y = 0, 1, 2, 3; x + y = 3) clusters and LDH-2 was suggested on the basis of by X-ray photoelectron spectroscopy. The excellent photoactive and oxidation performance of the Mo-6 cluster on the methylene blue degradation in an aqueous solution was determined in the dark, under UV light (lambda = 370 nm) or with the existence of H2O2. The combination of the LDH-2 with a high absorbability and recyclability and the Mo-6 cluster will be a promising candidate as a heterogenized homogeneous catalyst for removing organic pollutants.