| Abstract
| - Two kinds of sodium disilicate (hydrated α-sodium disilicate and kanemite) were reacted with C16TMA ions under various C16TMA/Si ratios to form mesostructured materials. The mesostructures derived from hydrated α-sodium disilicate are distinct from those derived from kanemite. Mesoporous silica from hydrated α-sodium disilicate is prepared at lower pH than that from kanemite without acid treatment at the C16TMA/Si ratio of 2.0, though the mesostructure is less ordered.
- Silica-based mesostructured materials are formed using hydrated α-sodium disilicate andhexadecyltrimethylammonium (C16TMA) chloride at various C16TMA/Si molar ratios, andcompared with those from kanemite. When the C16TMA/Si ratios are 0.2, 0.5, 0.7, and 1.0,2-D hexagonal structures are formed from hydrated α-sodium disilicate though the structuresare collapsed on calcination. Less ordered hexagonal structures with straight channelsarranged in one direction are formed when the C16TMA/Si ratio exceeds 1.0. In the case ofthe reactions of kanemite with C16TMA ions, lamellar mesostructures are formed at theratios higher than 0.5, whereas a 2-D hexagonal structure is formed only at the ratio of 0.2.Mesoporous silica (SSW-1) derived from hydrated α-sodium disilicate is prepared at lowerpH without acid treatment when the C16TMA/Si ratio is 2.0. The volume occupied by theheadgroups of C16TMA ions in hydrated α-sodium disilicate should be larger than that inkanemite because the distance between Si−O- sites in the bending direction of hydratedα-sodium disilicate is longer than that of kanemite due to the unique layered silicatestructure.
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