调控表面活性剂浓度制备单分散SBA-15介孔材料

Morphology-selective synthesis of monodispersed SBA-15 mesoporous silica by adjusting surfactant concentration

采用溶胶-凝胶水热法,调控反应参数和反应工艺制备SBA-15介孔材料。通过扫描电镜、透射电镜、X射线衍射以及氮气吸附-脱附分析表征表明,在一定范围,随着表面活性剂浓度增加,介孔材料SBA-15形貌出现由球形、陀螺形到米粒状的变化,介观有序度提高。在反应物料P123与Si物质的量比为0.012时,介孔材料的物性常数如晶面间距、比表面积、孔体积和最可几孔径较小。采用静态陈化-水热法研究不同表面活性剂浓度对介孔材料形貌演变的影响,为有效调控SBA-15介孔材料形貌提供必要依据。

With sol-gel hydrothermal method, SBA-15 mesoporous silica was prepared by adjusting reactive parameters and technology. The as-prepared samples were characterized by SEM, TEM, XRD and N2 adsorption-desorption. The results showed that the morphology of SBA-15 were evolved from sphere, gyroscopic to rice-like shape and its mesoporous order degree was enhanced with increase of surfactant concentration. The physical constants, such as crystal plane spacing, specific surface area, pore volume and most probable pore size were smaller while the molar ratio of reactants P123 to silica was O. 012. The relationship of different concentration surfactants and organic silicon hydrolysis-condensation body with SBA-15 morphological evolution were studied in static aging and hydrothermal process. It provided the necessary basis for effectively controlling morphology of the SBA-15 mesoporous silica.