Organic functionalization and morphology control of mesoporous silicas via a co-condensation synthesis method
Organic functionalization and morphology control of mesoporous silicas via a co-condensation synthesis method
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DOI：
10.1021/cm0210041
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发表时间：
2003-11-04
影响因子：
8.6
通讯作者：
Lin, VSY
中科院分区：
文献类型：
--
作者：
Huh, S;Wiench, JW;Lin, VSY
在低表面活性剂浓度条件下，采用共缩聚法制备了一系列具有MCM-41型结构、孔内有机官能团均一层的介孔二氧化硅材料。这种可重复的合成方法产生了高表面覆盖率，具有几个官能团，如伯胺、仲胺、尿素、异氰酸酯、乙烯基和腈。此外，在碱催化缩合过程中，有机烷氧基硅烷前体的存在对最终粒子的形状有很大影响。通过改变前驱体或其浓度，颗粒的形态被调节成不同的形状，包括不同尺寸的球状、管状和棒状。研究了导致特定颗粒形貌的合成过程，并推测了形状控制的机理。通过场发射扫描电子显微镜、透射电子显微镜、固体核磁共振波谱、热重分析和氮气吸附与脱附研究(BET等温线和BJH孔径分布测量)对材料的结构和功能进行了表征。
A series of new mesoporous silica materials with MCM-41 type of structure containing a homogeneous layer of organic functional groups inside the pores was prepared using a co-condensation method under low surfactant concentration condition. This reproducible synthetic approach resulted in high surface coverage with several functional groups such as a primary amine, secondary amine, urea, isocyanate, vinyl, and nitrile. In addition, the presence of organoalkoxysilane precursors during the base catalyzed condensation greatly influenced the final particle shape. By changing the precursor or its concentration, the particle morphology was tuned to various shapes, including spheres, tubes, and rods of various dimensions. The synthetic procedures that gave rise to the specific particle morphologies were investigated and the mechanism responsible for shape control was postulated. The structure and functionality of these materials were characterized by field-emission scanning electron microscopy, transmission electron microscopy, solid-state NMR spectroscopy, thermogravimetric analysis, and nitrogen adsorption and desorption studies (BET isotherms and BJH pore size distribution measurements).