| Abstract
| - Mesoporous silica with Ia3̄d structure has been successfully prepared by using mixed surfactants ofcommercially available nonionic block copolymer P123 (EO20PO70EO20) and anionic sodium dodecylsulfate (SDS) as structure-directing agents through an acid-catalyzed silica sol−gel process. XRD, TEM,and N2 sorption measurements show that the products have highly ordered bicontinuous cubic mesostructurewith high surface area (∼770 m2/g), large pore volume (∼1.5 cm3/g), and uniform pore size (∼10 nm).Effects of preparation parameters on the formation of the mesostructure have been extensively investigated.It is found that the molar ratios of SDS/P123 between 2.1 and 2.5 and that of silicic species to P123 inthe range from 40 to 75 are favorable for the formation of highly ordered Ia3̄d mesostructure. Prolonginghydrothermal treatment time leads to almost unchanged cell parameters of the products, whereas there isobvious increase of the pore sizes and pore volume. The results show that resultant template-freemesoporous silica products have excellent thermal stability, and they are more stable in N2 atmospherethan in air. Morphologies of the resultant materials can be further controlled by adding inorganic salt(such as Na2SO4) into the mixed surfactants system. Coral- and petaline-like mesoporous silica withcontinuous skeletons can be obtained. Understanding this synthesis system might be useful for economicaland large-scale production of mesoporous materials with controllable structures.
- Highly ordered Ia3̄d structured mesoporous silica with different morphologies has been successfully prepared by using commercially available anionic and nonionic mixed surfactants as structure-directing agents through an acid-catalyzed silica sol−gel process.
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