Preparation of High‐Quality MCM‐48 Mesoporous Silica and the Mode of Action of the Template

Abstract

Abstract Ultrastable MCM‐48 silica with Ia 3 d cubic structure was synthesized by using only the surfactant cetyltrimethylammonium tosylate (CTATos) as template at extremely low surfactant concentration (CTATos/SiO 2 = 0.068). Characterization by small‐angle X‐ray diffraction (XRD), nitrogen adsorption, and high‐resolution transmission electron microscopy (HRTEM) clearly shows that the obtained MCM‐48 silica has a highly ordered structure and large surface area (ca. 1281 m 2 /g) and pore volume (ca. 1.07 cm 3 /g). The regular cubic arrays were well retained even after this material was calcined at a high temperature of 900 °C for 3 h or heated at reflux in boiling water for 12 h. The Fourier transform infrared (FTIR) spectrum, thermogravimetric analysis (TG), and chemical analysis provide strong evidence that the formation of MCM‐48 is attributed to the retention of tosylate (Tos – ) counteranions of the surfactant in the interface between surfactant and silicate. The current synthetic strategy is suitable for routine and large‐scale preparations of mesoporous silica with different topological structures.