Control of structure, pore size and morphology of three-dimensionally ordered mesoporous silicas prepared using the dicationic surfactant [CH3(CH2)15N(CH3)2(CH2)3N(CH3)3]Br2

摘要: The synthesis of mesoporous silicas in the presence dicationic gemini surfactant [CH3(CH2)15N(CH3)2(CH2)3N(CH3)3]Br2 (C16-3-1) has been investigated at low temperatures (−4 °C) under basic and acidic conditions. Under conditions, SBA-2 phase (based on a close-packed arrangement micelles exhibiting frequent stacking faults) is observed, with hollow sphere morphology. strongly SBA-1 (Pmn) family phases close packing micelles) are depending silicate content original gel. Conditions which pure hexagonally end member (P63/mmc) formed have identified. prepared well-defined morphologies. adsorption nitrogen hydrocarbons cyclopentane mesitylene reveal that media cage structure where cages linked through small (<4 A) micropores, whereas larger pores after calcination. poorly ordered SBA-2, using C16-3-1 able to adsorb (diameter ca. 8 A), hexagonal series conditions 5 but not mesitylene.