摘要
以阳离子表面活性剂十六烷基三甲基溴化铵为模板、以正硅酸乙酯(TEOS)为前驱体、三乙醇胺为催化剂、正己烷为有机油相,使用油水两相体系实现树枝状介孔氧化硅(Dendritic mesoporous silica, D-mSiO_2)在实心氧化硅(Solid silica, sSiO_2)微球表面的连续均匀包覆,制备出具有核/壳结构的sSiO_2/D-mSiO_2复合微球。使用场发射扫描电子显微镜(FESEM)、高分辨透射电子显微镜(HRTEM)、傅里叶变换红外光谱(FTIR)、X射线衍射(XRD)和氮气吸附/脱附等手段表征了样品的结构。FESEM和TEM结果表明,在复合微球的氧化硅壳层中有大量的放射树枝状开放介孔,其孔道垂直于内核表面呈辐射状,改变TEOS用量可调控包覆层的厚度。小角衍射的结果显示,这种类型的树枝状介孔孔道的有序性比较差,孔道的平均孔径分布在7～9 nm。随着搅拌速率(50～500 r/min)的提高,D-mSiO_2壳层厚度(5～60 nm)呈先增大后减小趋势。还讨论了树枝状介孔氧化硅核壳复合微球的形成机制及其影响因素。
Core/shell structured composite microspheres of sSiO2/D-mSiO2 composed of solid silica（sSiO2） as core and dendritic mesoporous silica（D-mSiO2） as shell were synthesized via an oil-water biphase stratification approach with cetyltrimethylammonium bromide（CTAB） as template, tetraethylorthosilicate（TEOS） as precursor, Triethanolamine（TEA） as catalyst and n-hexane as emulsion agent. The synthesized products were characterized by means of field emission scanning electron microscopy（FESEM）, high resolution transmission electron microscopy（HRTEM）, Fourier transform infrared spectroscopy（FTIR）, X-ray diffractometer（XRD）, and nitrogen adsorption/desorption measurements. As revealed by FESEM and TEM that there existed plenty of radiate-dendritic-like open meso-channels, which were perpendicular to the s SiO2 sphere surface.The thicknesses of D-mSiO2 shell could be controlled by adjustingthe TEOS amount. Low-angle XRD analyses suggested that the mesochannles in the shells exhibit poor degree of order, and the average pore diameter was 7～9 nm. Moreover, the D-mSiO2 shell thicknesses（5～60 nm） increased firstly and then decreased with the increase of stirring rate（50～500 r/min）. Finally,the formation mechanism for the mesoporous shells with radiate-dendritic-like open meso-channels of composite microspheres was also discussed.
作者
左长智
陈杨
陈爱莲
ZUO Changzhi;CHEN Yang;CHEN Ailian(School of Materials Science and Engineering,Changzhou University,Changzhou 213164,China;School of Mechanical Engineering,Changzhou University,Changzhou 213164,China)
出处
《材料研究学报》
EI
CAS
CSCD
北大核心
2018年第10期791-800,共10页
Chinese Journal of Materials Research
基金
国家自然科学基金(51405038
51575058
51875052)~~
关键词
无机非金属材料
介孔氧化硅
树枝状孔道
核壳结构
复合微球
inorganic non-metallic materials
mesoporous silica
dendritic mesoporous channels,core/shell structure
composite microspheres
作者简介
左长智，男，1991年生，硕士生;通讯作者陈杨，副教授，cyjpu@126．com，研究方向为复合材料及摩擦学
