阶层多孔二氧化硅块体材料的制备与表征  

Preparation and Characterization of Hierarchically Porous Silica Monoliths

作　　者：郭兴忠[1] 单加琪 丁力[1] 于欢[1] 章肖祺 杨辉[1] 

机构地区：[1]浙江大学材料科学与工程学院,杭州310027

出　　处：《无机化学学报》2015年第4期635-640,共6页Chinese Journal of Inorganic Chemistry

基　　金：国家自然科学基金(No.51372225);浙江省自然基金(No.LY13B010001)资助项目

摘　　要：以正硅酸甲酯（TMOS）为前驱体、0.01 mol·L-1盐酸为催化剂、聚环氧乙烷（PEO,分子量为10 000）为相分离剂、环氧丙烷（PO）为凝胶促进剂、十二烷基硫酸钠（SDS）为造孔剂,采用溶胶-凝胶伴随相分离制备阶层多孔二氧化硅块体材料,利用差热分析（DTA）、热重分析（TG）、傅里叶变换红外（FT-IR）光谱、扫描电镜（SEM）、X射线衍射（XRD）、N2吸附/脱附装置等测试技术对所制得的阶层多孔块体进行了表征,探究造孔剂SDS对大孔和介孔结构的影响机理。研究表明：SDS在凝胶过程中以胶束的形式进入到骨架中形成介孔孔道;当SDS为0.21 g时,块体材料的阶层多孔结构最优,大孔孔径为1-3μm,介孔孔径为4-5 nm,比表面积为650 m2·g-1;800℃热处理后,大孔结构和骨架上的介孔基本保持,比表面积仍能达到421 m2·g-1,体现出良好的热稳定性。Hierarchically porous Si O2 monoliths were prepared via sol-gel process accompanied by phase separation with tetramethoxysilane（TMOS） as precursor, poly（ethylene oxide）（PEO） as phase separation inducer,propylene oxide（PO） as gelation agent, 0.01 mol·L-1hydrochloric acid as catalyst, and twelve sodium dodecyl sulfate（SDS） as mesopore forming agent. The resultant monoliths were characterized by differential thermal analysis（DTA）, thermogravimetry（TG）, Fourier transform infrared（FT-IR） spectroscopy, X-ray diffraction（XRD）,scanning electron microscopy（SEM）, and nitrogen adsorption/desorption analysis, and the effects of SDS on the macroporous and mesoporous structure of the monoliths were investigated. The results show that the SDS uniformly distributes into the skeletons in the form of micelles, which leads to the formation of mesopores. When SDS is 0.21 g, the optimum hierarchically porous structure is obtained with macropore size of 1-3 μm, mesopore size of 4-5 nm, and BET specific surface area as high as 650 m2·g-1. After heat treatment at 800 ℃, macroporous structure and mesopores on the skeleton basically remain, and the BET specific surface area still maintains at421 m2·g-1, which indicates good thermal stability.

关 键 词：溶胶-凝胶 相分离 氧化硅 多孔块体 造孔剂 

分 类 号：O613.72[理学—无机化学]