A facile route to synthesize mesoporous SBA-15 silica spheres from powder quartz

A facile route is demonstrated to synthesize mesoporous SBA-15 silica spheres from powder quartz as an inexpensive silica source. P123 dissolved in an HCl solution was used as a structure-directing agent followed by hydrothermal processing of the product at 100 °C for 24 h. No other additives were used in the preparation. The morphology and structural order of the samples were strongly influenced by the HCl concentration (MHCl = 2-4.5) of the P123 solution. At MHCl < 2.5 the SBA-15 silica morphology was rod-like with a length that decreased and a diameter which increased with increasing HCl concentration. As MHCl increased between 3 and 4, the morphology became increasingly sphere-like leading to well-formed SBA-15 silica spheres of size ranging from 1 to 4 µm. At MHCl = 4.5 a less ordered mesoporous structure was observed.