Publication
Title
The influence of the $Ti^{4+}$ location on the formation of self-assembled nanocomposite systems based on $TiO_{2}$ and Mg/Al-LDHs with photocatalytic properties
Author
Abstract
 Herein, we report the formation of TiO2/LDH self-assembled nanocomposite systems using the memory effect property of the layered clay-type materials. Two different synthesis approaches, based on the modification of the initial brucite-like sheets composition, were used in order to investigate the influence of the Ti4+ location on the quality of the final products: the reconstruction of a calcined MgAl-LDH in a TiOSO4 center dot xH(2)O aqueous solution and the reconstruction of a calcined MgAlTi-LDH in aqueous solution. The reconstruction process, monitored using X-ray diffraction, IR spectroscopy, UV-vis diffuse reflectance spectroscopy, SEM and thermal analysis, produced different structural changes strongly related with the brucite-like sheets composition. The photocatalytic activity of the obtained nanocomposite systems was evaluated for the degradation of the methyl-orange (MO) dye. An intimate contact has been created between the anatase and the brucite-like sheets in the nanocomposite systems, which had a direct influence on the HO center dot radical production enhancing thus the photocatalytic performances. When comparing the as-synthesized catalysts, the MgAlTi-LDH solid manifests very powerful photocatalytic effect due to the segregation of small, well defined TiO2 nanoparticles on the highly hydroxilated layered surface. Up to 93% of the dye could be removed by a TiO2/LDH-type nanocomposite system. Controlled thermal treatment of photocatalytic systems allowed us to tailor the quality of the photocatalytic active sites deposited on the layered support. The use of the TiO2/LDHs nanocomposites showed multiple advantages highlighted by the increased activity per mass, higher efficiencies at a decreased solid/liquid ratio, decreased reaction times, reduced agglomeration and easy to separate at the end of the processes. (C) 2013 Elsevier B.V. All rights reserved.
Language
English
Source (journal)
Applied catalysis : B : environmental. - Amsterdam
Publication
Amsterdam : 2013
ISSN
0926-3373
Volume/pages
134(2013), p. 274-285
ISI
000316583500032
Full text (Publisher's DOI)
Full text (publisher's version - intranet only)
UAntwerpen
 Faculty/Department Research group Publication type Subject Affiliation Publications with a UAntwerp address