A negative deviation from Porod’s law in SAXS of organo—MSU—X

• 作者: B.Z.Dong D.Wu J.Wang Y.H.Sun Y.J. Y.J.Gong Y.Liu Z.H.Li
• 来源期刊: 北京同步辐射装置：英文版
• 学科: 工学
• 关键词: 中孔材料 SAXS 小角X射线散射分析 界面层 结构特征 有机中孔分子筛 负偏差 Porod法
• 年，卷（期）: 2001,（2）
• 页码范围: 20-25
• 页数: 6页
• 分类号: TQ424.25

摘要

Small-angle X-ray scattering(SAXS)using synchrotron radiation as X-ray source has been employed to charactcizc the microscopic structrure of organo-modified mesoporous molecular sieves(organo-MSU-X)prepared by a one-pot template-directed synthesis.It is shown that the SAXS profile is hardly constant with Porod’s law showing a negative slope,i.e.,negative deviation.This suggests that there is diffuse interfacial layer located between the pores and the matrix.This suggests that the organic groups remain covalently linked to the matrix,as indicated by ^29SiCP MAS NMR and FT-IR.The average thickness of the interfacial layer was found to be about 1nm for each of the three samples with different kinds and the same amounts(20? of organic groups.This kind of material has also been proved to possess both surface and mass fractal structure of the amophous porous silica materials.2001 Elsevier Science B.V.All rights reserved.