Direct Syntheses of Ordered SBA-15 Mesoporous Silica Containing Sulfonic Acid Groups

✍ Scribed by Margolese, D.; Melero, J. A.; Christiansen, S. C.; Chmelka, B. F.; Stucky, G. D.

• Book ID: 111948960
• Publisher: American Chemical Society
• Year: 2000
• Tongue: English
• Weight: 209 KB
• Volume: 12
• Category: Article
• ISSN: 0897-4756
• DOI: 10.1021/cm0010304

✦ Synopsis

A simple procedure has been developed for the syntheses of functionalized mesoporous materials with sulfonic groups involving the co-condensation of tetraethoxysilane and mercaptopropyltrimethoxysilane in the presence of block copolymers and hydrogen peroxide under acidic conditions. The modified SBA-15 materials show hexagonal mesoscopic order and pore sizes up to 60 Å, with acid exchange capacities ranging from 1 to 2 mequiv of H + /g of SiO 2 , surface areas up to 800 m 2 /g, and excellent thermal and hydrothermal stabilities. The formation of the sulfonic groups during co-condensation of the silica species coincides with enhanced mesoscopic ordering and changes in the adsorption properties of the final materials. 31 P MAS NMR measurements of chemically adsorbed triethylphosphine oxide confirm the presence of Bro ¨nsted acid centers that are stronger that those found in Al-MCM-41. Finally, this procedure has been generalized to prepare functionalized mesoporous solids containing sulfonic groups and other organic moieties.