(1. 常州大学 材料科学与工程学院,常州 213164;
2. 常州大学 机械工程学院,常州 213164)
摘 要: 在室温条件下以十六烷基三甲基溴化铵为表面活性剂制备亚微米级介孔二氧化硅(mSiO2)微球,通过小角XRD、FESEM、TEM和孔分布测试等手段对样品进行结构表征。结果表明:所得mSiO2微球的粒径为(316±11) nm,样品内部存在蠕虫状放射状介孔孔道,其孔径多集中在2.5 nm。利用AFM力曲线测试技术对单个mSiO2微球的弹性响应进行评价,通过解析所记录的力—位移曲线,分别结合Hertzain模型和Sneddon模型对样品的压缩弹性模量进行拟合计算。利用Hertzain弹性接触模型计算得出的弹性模量平均值为5.30 GPa,在Sneddon模型条件下获得的弹性模量平均值为16.50 GPa,与现有文献中关于介孔氧化硅薄膜材料弹性模量的报道值(3~16 GPa)基本相当。
关键字: 介孔氧化硅微球;放射状孔道;表面活性剂;压缩弹性模量
(1. School of Materials Science and Engineering, Changzhou University, Changzhou 213164, China;
2. School of Mechanical Engineering, Changzhou University, Changzhou 213164, China)
Abstract:The submicrometer mesoporous silica (mSiO2) microspheres were synthesized using cetyltrimethylammonium bromide as surface active agent under room temperature. The structural characteristics of the obtained samples were characterized by low-angle X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy and nitrogen adsorption-desorption methods. The results show that the particle size of mSiO2 microspheres with worm-like and radial channels is (316±11) nm, and the pore diameter of mesochannels is 2.5 nm. The elastic responses of mSiO2 microspheres deposited on a rigid substrate were evaluated by using an atomic force microscope. The compressive elastic modulus of individual microsphere was fitted and calculated by analyzing the AFM force-displacement curves on the basis of the Hertzain and Sneddon contact models. The results show that the average elastic moduli are 5.30 (Hertzain model) and 16.50 GPa (Sneddon model), which are comparable with the reported elastic moduli for mesoporous silica film materials (3-16 GPa).
Key words: mesoporous silica microsphere; radial channel; surface active agent; compressive elastic modulus