Aerosol-Assisted Controlled Packing of Silica Nanocolloids: Templateless Synthesis of Mesoporous Silicates with Structural Tunability and Complexity
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- 作者：Kyungmin Min ; Chang Hyuck Choi ; Myoung Yeob Kim ; Minkee Choi
- 刊名：Langmuir
- 出版年：2015
- 出版时间：January 13, 2015
- 年：2015
- 卷：31
- 期：1
- 页码：542-550
- 全文大小：581K
- ISSN：1520-5827
文摘
A template-free synthesis method for mesoporous and macro-/mesoporous hierarchically porous silicates with remarkable structural tunability and complexity is presented. SiO2 nanocolloids having diameters of 3.0鈥?9 nm were prepared as a primary building block by using extended St枚ber synthesis, and they were subsequently assembled by an aerosol-assisted drying. The silica pore structure can be rationally controlled depending on the initial diameter of SiO2 colloids and the aerosol-assembly temperature that determines the packing density of SiO2 colloids (i.e., amounts of packing defects) in the resultant materials. The present method could produce mesoporous silica spheres with remarkable pore-structural tunability (291 < BET surface area <807 m2 g鈥?, 0.42 < pore volume <0.92 cm3 g鈥?, 3.1 < pore size <26 nm). Hierarchically porous materials can also be synthesized by the evaporation-induced phase separation of solvent medium during the aerosol-assisted assembly of SiO2 colloids. By adding aluminum and Pt precursors into the SiO2 colloid suspensions before the aerosol-assisted assembly, mesoporous aluminosilicates supporting uniform Pt nanoclusters (鈭? nm) can also be synthesized. This indicates that the synthesis strategy can be used for the direct synthesis of functional silicate materials.