A cationic surfactant assisted selective etching strategy to hollow mesoporous silica spheres
A cationic surfactant assisted selective etching strategy to hollow mesoporous silica spheres
复制标题
阳离子表面活性剂辅助空心介孔二氧化硅球的选择性蚀刻策略
DOI：
10.1039/c0nr00893a
复制
发表时间：
2011-01-01
期刊：
影响因子：
6.7
通讯作者：
Zheng, Nanfeng
中科院分区：
文献类型：
--
作者：
Fang, Xiaoliang;Chen, Cheng;Zheng, Nanfeng
中空介孔二氧化硅微球最近引起了越来越多的关注。然而，对于基础研究和实际应用来说，有效地合成具有可控的、定义良好的孔结构的均匀的中空介孔微球仍然是一个巨大的挑战。本文提出了一种简单有效的“阳离子表面活性剂辅助选择性刻蚀”的合成方法，用于制备具有虫孔状或定向介孔壳的高质量中空介孔二氧化硅微球。所制备的中空介孔二氧化硅微球具有较大的比表面积、较高的孔容和可控的结构参数。我们的实验表明，阳离子表面活性剂在中空介孔结构的形成中起着关键作用。提出了一种由阳离子表面活性剂加速刻蚀固体二氧化硅，再由阳离子表面活性剂引导溶解的二氧化硅物种再沉积的形成机理。此外，该策略还可以推广为一种通用策略，将二氧化硅涂层复合材料转变为具有虫孔状或定向介孔壳层的蛋黄壳结构。
Hollow mesoporous silica spheres have recently attracted increasing attention. However, effective synthesis of uniform hollow mesoporous spheres with controllable well-defined pore structures for fundamental research and practical applications has remained a significant challenge. In this work, a straightforward and effective "cationic surfactant assisted selective etching" synthetic strategy was developed for the preparation of high-quality hollow mesoporous silica spheres with either wormhole-like or oriented mesoporous shell. The as-prepared hollow mesoporous silica spheres have large surface area, high pore volume, and controllable structure parameters. Our experiments demonstrated that cationic surfactant plays critical roles in forming the hollow mesoporous structure. A formation mechanism involving the etching of solid SiO2 accelerated by cationic surfactant followed by the redeposition of dissolved silica species directed by cationic surfactant is proposed. Furthermore, the strategy can be extended as a general strategy to transform silica-coated composite materials into yolk-shell structures with either wormhole-like or oriented mesoporous shell.