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

Abstract

Mesoporous titanium dioxide (TiO _2 ) is one of the most studied mesoporous materials considering its special character and various applications. In the present work, mesoporous TiO _2 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 TiO _2 anatase phase. The crystallite size of all samples was found to vary in the range of 8.60 nm to 13.61 nm. The transition temperature of the anatase phase was increased to several Celsius degrees since TiO _2 was fabricated with a template assistant. The surface area of the mesoporous TiO _2 was increased in the range of 93 m ^2 .g ^−1 (CTAB) − 116.8 m ^2 .g ^−1 (MTAB). These values were larger than the TiO _2 synthesized without a template (72 m ^2 .g ^−1 ). The total pore volume was also increased between 0.1704 cm ^3 .g ^−1 (CTAB) and 0.300 cm ^3 .g ^−1 (MTAB), while the TiO _2 synthesized without a template was only 0.161 cm ^3 .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.

Keywords

• titanium oxide
• mesoporous materials
• soft-template
• cationic surfactants