Synthesis and Characterization of Mesoporous Silica Templated by Amphiphilic RTILs

Abstract

This article reports a novel preparation of mesoporous silica with series of 1-alky-3-methylimidazolium bromide (C_nMIM)Br (n = 12, 14, 16), a kind of amphiphilic room-temperature ionic liquids (RTILs), as a template via a sol-gel nanocasting technique. The pore morphology and structures of these mesoporous silica were characterized by Transmission electron microscopy (TEM). The results show that the RTIL bearing longer alkyl chain is preferred to form the mesoporous silica material with bigger pores. (C₁₆MIM)Br has been chosen to study how the various influencing factors affect the synthesis and structure of the mesoporous silica material, such as the acid concentration, the solling time, the gelling time and the calcination time. N₂ adsorption-desorption isotherms measurement was used to characterize the pore size distribution and BET surface area. The results indicate that all of the factors can make an influence on the preparation of the mesoporous silica, which is more sensitive to the concentration of the acid.

Keywords:

• Mesoporous silica
• room-temperature ionic liquid
• sol-gel nanocasting technique

This work was financially supported by the National Natural Science Foundation (NO. 50472069) and Doctorate Funds of China (NO. 2004022054).

Notes

^a Calculated from the adsorption portion of the N₂ adsorption desorption isotherm.