晶化温度对Al-SBA-15复合材料结构的影响

Influence of Crystallization Temperatures on the Structure of Al-SBA-15 Composite Mesoporous Materia

摘要: 采用水热直接合成法制备了介孔分子筛Al-SBA-15复合材料,详尽地考察了晶化温度对其结构的影响,并利用N2吸附、扫描电镜(SEM)、X-射线衍射(XRD)、傅里叶红外光谱(FT-IR)等手段进行了表征.研究发现,随着晶化温度的升高:Al-SBA-15复合材料的结构有序性增强,晶胞参数和平均孔径逐渐增大;比表面先增大后减小,100℃晶化样品比表面最大(611 m2/g);孔容亦是先增后降,120℃晶化样品达最大值(1.01 cm3/g);晶化温度较低时,其对壁厚的影响不甚明显,但温度过高时,则壁厚显著降低(40~100℃晶化壁厚约5 nm,140℃晶化时则锐减至1.15 nm),同时结构有序性变差.

Abstract: Mesoporous molecular sieves SBA-15 composite materials doped with alumina was synthesized via a direct hydrothermal method.The samples were analyzed by N2 adsorption-desorption,SEM,XRD and FT-IR.The results showed that all prepared Al-SBA-15 materials retained the characteristic meso-structure of SBA-15.Nitrogen sorption measurement showed that the pore size of the samples can be tuned from 3.57 to 9.67 nm by simply adjusting crystallization temperature from 40 to 140 ℃.The sample crystallized at 100 ℃ exhi...