Improvement in properties of mesoporous MCM-41 spheres using buffer solutions as additives under room temperature

Abstract

MCM-41 spheres of 300–400 nm size were synthesized using a modified Stöber method at room temperature. We found that the pH value changed with the hydrolysis of tetraethyl orthosilicate in the process, which was not conducive to the formation of ordered mesoporous structures. Therefore, buffer solutions (NaH₂PO₄ + NaOH, Glycine + NaOH, KCl + NaOH) were added to the system and the pH was successfully stabilized. MCM-41 particles synthesized using the buffer solution have a more ordered mesoporous structure. Results demonstrate that the BET surface area of MCM-41 improved from 1490 ± 7 to 1672 ± 9 m²/g after adding the buffer solution. The efficacy of this synthetic method may be attributed to the stabilized pH value and enhanced effect of H₂NCH₂COO ions on the formation of ordered templates.

Graphical Abstract

Keywords:

• MCM-41 sphere
• buffer solutions
• TEOS hydrolysis
• surfactant assemblies
• specific surface area

Acknowledgments

The authors thank Dr. Bu Xu for polishing the manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).