毫米级轻质高强度多孔二氧化硅球的制备与表征

Preparation and Characterization of Strong-lightweight Porous Silica Spheres in Millimeter Scale

以F127和十六烷基三甲基溴化铵(CTAB)为模板,正硅酸乙酯(TEOS)为硅源,在液体石蜡/水(W/O)体系中通过自组装合成了毫米级轻质高强度多孔二氧化硅球.采用激光粒度分析仪、透射电子显微镜(TEM)、扫描电子显微镜(SEM)、氮气吸附-脱附分析仪及纳米压痕仪对合成的产物进行了表征.结果表明,合成产物是直径为(1.40±0.20)mm的球形颗粒,球内存在大量多级孔洞,从2 nm到几十纳米的多级孔径并存,样品的Brunauer-Emmett-Teller(BET)比表面积为498.00 m2/g.另外,毫米级多孔二氧化硅球的表观密度为0.44 g/cm3,硬度与弹性模量分别为549.00 MPa和9.19 GPa.

Strong-lightweight porous silica spheres in millimeter scale were synthesized using cationic surfactant hexadecyltrimethyl ammonium bromide（ CTAB） and nonionic surfactant F127 as templates,tetraethyl orthosilicate（ TEOS） as silica source in liquid paraffin / water（ W / O） system via self-assembly. The samples were characterized by means of laser particle size analyzer,scanning electron microscopy（ SEM）,transmission electron microscopy（ TEM）,nitrogen adsorption-desorption measurments and nanoindentor. The results indicate that spheres with diameter of（ 1. 4 ± 0. 2） mm are obtained,the hierarchical pores with the size from 2nm to tens of nanometers are within the samples,and the BET surface area of the sample is 498. 00 m2/ g. In addition,the bulk density of the sample is just 0. 44 g / cm3,but its hardness is up to 549. 00 MPa and elasticity modulus sums up to 9. 19 GPa.