The effect of the number of hydrophobic tails of cationic ammonium surfactants on mesoporous TiO₂ synthesized

Abstract

Mesoporous titanium dioxide (TiO2) is one of the most studied mesoporous materials considering its special character and various applications. In the present work, mesoporous TiO2 was synthesized by a sol-gel method employing different hydrophobic tails of ammonium cationic surfactants templates. The prepared samples were characterized by various techniques. The XRD profiles confirmed that all samples crystallized into the TiO2 anatase phase. The crystallite size of all samples was found to vary in the range of 8.60nm nm to 13.61 nm. The transition temperature of the anatase phase was increased to several Celsius degrees since TiO2 was fabricated with a template assistant. The surface area of the mesoporous TiO2 was increased in the range of 93 m2.g-1 (CTAB) - 116.8 m2.g-1 (MTAB). These values were larger than the TiO2 synthesized without a template of 72 m2.g-1. The total pore volume was also increased between 0.1704 cm3.g-1 (CTAB) and 0.300 cm3.g-1 (MTAB), while the TiO2 synthesized without a template was only 0.161 cm3.g-1. Using CTAB and DDAB yield a uniform mesopore size distribution. MTAB tends to produce non-uniform pore of the mesoporous system. The soft-templating method opens up new possibilities for synthesizing mesoporous metal oxides.