Particle morphology and microstructure in the mesoporous silicate SBA-2

The mesoporous solid SBA-2, prepared at room temperature in alkaline pH using the gemini surfactant [CH3(CH2)15N(CH3)2(CH2)3N(CH3)3]2+ can adopt hollow sphere (ca. 100 μm diameter), flat plate (50 μm across) and small sphere (1–2 μm diameter) morphologies. Plates appear to be formed directly by fracturing of the hollow spheres. The nanostructure of these materials is consistent with templating around close packed micelles. X-Ray diffraction and high resolution imaging show that the structure of these preparations ranges from mainly hexagonal to mainly cubic close packing.