Please cite this article in press as: E.M. Seftel, et al., Photocatalytic removal of phenol and methylene-blue in aqueous media using TiO 2 @LDH clay nanocomposites, Catal. Today (2014), http://dx. a b s t r a c tHerein, we report the formation of a series of nanocomposites composed of LDH structures and TiO 2 with anatase crystal phase. The structure of the LDH clay was modulated by the insertion of different di-, trior tetravalent cations, such as Zn 2+ , Cu 2+ , Al 3+ , Fe 3+ or Ti 4+ , within the brucite-like sheets. Afterwards, the anatase seeds were deposited onto the LDH clays, obtaining new nanocomposite systems with tailored photocatalytic activity. In this way, the photoresponsive properties of the final nanocomposites were shifted from the UV to the visible range of the solar spectrum. The obtained nanocomposites were tested for the degradation of different organic pollutants, like phenol and methylene blue, under UV and visible light in aqueous media with different pH. The kinetic study showed that the TiO 2 @LDH nanocomposites are efficient for the phenol (and its intermediary species catechol and hydroquinone) and methylene blue photocatalytic degradation under both UV and Vis light illumination.

a b s t r a c tThe work reported involves a detailed characterization study on a series of nanocomposite systems comprising layered double hydroxides and TiO 2 seeds with anatase crystal structure. The TiO 2 /LDH nanocomposite structural and textural features were varied by the isomorphous substitution within the LDH sheets network of the divalent cations (Zn 2+ by Cu 2+ ) and the trivalent cations (Al 3+ by Fe 3+ or Ti 4+ ) respectively. In depth characterization was obtained by using a combination of XRD, N 2 sorption, SEM, TEM/EDX and SAXS characterization techniques in order to maximize the structural information of the parent and modified LDH materials. An increase material compactness on the TiO 2 /LDH nanocomposites was observed due to the accommodation of the TiO 2 seeds within the mesopores together with a surface coating. SAXS observations indicated the modification of the morphology of the parent LDH samples by the addition of the TiO 2 seeds suggesting the rearrangement of the LDH layers during the nanocomposite formation.