Effect of pH in Mesoporous Silica Synthesis


  • Farid M. Hota Physical Chemistry, Department of Chemistry, Faculty of Science, Sirte University, Sirte, Libya
  • Wafia M. Emhalhal Organic Chemistry, Department of Chemistry, Faculty of Science, Sirte University, Sirte, Libya,


mesoporous, triblock copolymer, pH, 2D-hexagonal, gellike, pore size controlling


Mesoporous silica was tailored by using diluted triblock copolymer F127. The synthesised silica structure was characterized by TEM and N2 sorption isotherm.3D- hexagonal arrangement of 5-30 nm pore sizes obtained. The pore sizes and ordering were affected by pH change in synthesis mixture. Although well-ordered hexagonal arrangement of mesoporous was dominant in acidic conditions, the mesoporous silica synthesized in neutral or basic conditions indicates gel-like structures with no mesoporous. The presence of low pH sol-gel reaction, followed by high pH reaction through addition of alkaline during synthesis, not only produced mesoporous materials, but also provided pore size controlling.


D. Antonelli, J. Ying, Curr. Opin. Colloid Interface Sci. 1 (1996) 523.

C.T. Kresge, M. E. Leonowicz, W.J. Roth, J. C. Vartuli, J. S. Bleck, Nature 539 (1992) 710.

C. G. Goltner, M. Antoniette, Adv. Mater. 9 (1997) 431.

J. M. Kim, J. H. Kwak, S. Jim, R.Rwoo, J. Phys. Chem. 99 (1995)16742.

S. A. Bagshaw, E. Prouzet, T. J. Pinnavaia, science 269 (1995)1242.

E. Prouzet, T. J. Pinnavia, Angew. Chem. Int. Ed. Engl. 36 (1997) 516.

A. C. Voegtlin, F. Ruch, J. L. Guth, J. Patarin, L. Huve, Microporous Mater. 9 (1997) 95.

P. Schmidt-Winkel, P. Yang, D. I. Margolese, B. F. Chmelka, G. D. Stucky, Adv. Mater. 11 (1999)303.

J.M.Kim,Y-J.Han,B.F.Chmelka, G. D. Stucky, Chem. Commun.2 (2002) 437.

P. Schmidt-Winkel, W. W. Lukens Jr., D. Zhao, P. Yang, B.F. Chmelka,G. D. Stucky, J. Am. Chem. Soc. 121 (1999) 254.

P. Alexandridis, T. A. Hatton, Colloids Surf. A 96 (1995) 1.

D. Zhao, Q. Huo, J. Freg, B.F.Chmelka, G. D. Stucky, J. Am. Chem. Soc. 120 (1998) 6024.

P. Holmqvist, P. Alexandrridis,B. Lidman, Macromolecules 30 (1997) 6788.

W. L. Huang, K. M. Liang, S. R.Gu, J. Non-Cryst. Solids 258 (1994) 234.