Photocatalytic behavior of nanosized TiO2 immobilized on layered double hydroxides by delamination/restacking process

Efficient immobilization of TiO2 nanoparticles on the surface of Mg2Al-LDH nanosheets was performed by delamination/restacking process. The structural and textural properties of as-prepared nanocomposite were deeply analyzed using different solid-state characterization techniques such as: X-ray powder diffraction, Fourier transform infrared spectroscopy, and Raman spectroscopies, chemical analysis, X-ray photoelecton spectroscopy, N-2 adsorption-desorption, and electronic microscopy. The photocatalytic properties of immobilized TiO2 nanoparticles on Mg2Al were investigated using the photodegradation of two model pollutants: Orange II and 4-chlorophenol, and compared with pure colloidal TiO2 solution. It appears that Orange II photodegradation was systematically faster and more efficient than 4-chlorophenol photodegradation regardless of the medium pH. Moreover under slightly basic conditions, even if the TiO2 photocatalytic efficiency decreases, photodegradation performed in presence of easily recovered TiO2/Mg2Al1.5 nanocomposite gives rise to comparable or better results than pure TiO2.