Synthesis and characterization of mesoporous titanium dioxide using self-assembly of sodium dodecyl sulfate and benzyl alcohol systems as templates

Abstract

Mesoporous TiO 2 materials have been synthesized with the aid of benzyl alcohol (BA) as cosurfactant along with an anionic surfactant sodium dodecyl sulfate (SDS) as the template/structure directing agent (SDA). The synthesis was carried out both with and without the use of BA in the presence of an anionic surfactant (SDS) or cationic (cetyltrimethyl ammonium bromide, CTAB) to optimize the synthesis conditions. SDAs were removed from the as-synthesized material through ethanol–acetate extraction or by a newly developed borohydride reduction technique described herein. The resulting materials were characterized by XRD, TEM, FE-SEM, nitrogen sorption, UV–visible and FTIR spectroscopic tools. The use of BA along with SDS assisted the formation of the mesophase, whereas by using SDS alone or by using cationic surfactant CTAB as SDA along with BA, no TiO 2 mesophase formation was observed. These mesoporous TiO 2 materials showed very high surface area along with the existence of mesopores having broad pore size distributions. A model has been proposed to rationalize the synthesis of mesoporous TiO 2 materials by using self-assembly of surfactant (SDS or CTAB) and cosurfactant (BA) mixtures as templates.