颗粒模板法制备大孔Al_2O_3材料  

Preparation of Macroporous Al_2O_3 by Template Method

作　　者：王晓冬[1] 董鹏[1] 陈胜利[1] 

机构地区：[1]中国石油大学重质油国家重点实验室,北京102249

出　　处：《物理化学学报》2006年第7期831-835,共5页Acta Physico-Chimica Sinica

基　　金：国家重点基础研究发展规划(973)项目(2004CB217808);国家自然科学基金(20376046)资助

摘　　要：采用颗粒模板法制备了大孔氧化铝(Al2O3)材料.扫描电子显微镜(SEM)结果显示,大孔Al2O3结构中的大孔呈“囊泡状”且孔道的贯通性较差.Zeta电位测量表明,共沉积条件下聚苯乙烯(PS)和Al2O3两种胶体颗粒带有相反的电荷,在静电引力作用下先发生了吸附,再沉积在一起.吸附在PS微球表面的Al2O3纳米颗粒形成的吸附层是导致大孔呈“囊泡状”和孔道不贯通的主要原因.采用聚二烯丙基二甲基氯化铵(PD)溶液对PS胶体微球带电性质进行了改性,PS微球的Zeta电位由-44.36mV变成了+37.41mV,进而消除了沉积过程中二元颗粒间的吸附现象.扫描电子显微镜显示,大孔样品中“囊泡状”大孔消失,同时孔道贯通性得到改善.Macroporous material of Al2O3 was prepared through mixing a Al2O3 sol with polystyrene （PS） particles as templates, drying the suspension, and finally calcining it to remove the templates. The measurement obtained from the scanning electron microscopy （SEM） showed that the formed macroporous materials had a vesicle-like structure and most of the voids left by the templates were isolated from each other. The Zeta-potential value indicated that the PS spheres carded negative charges, whereas the alumina particles carried positive charges. During the preparation of macroporous Al2O3, the Al2O3 colloidal particles were adsorbed on the surface of the PS particles, and the PS with the shell of Al2O3 particles played the role of templates, resulting in the formation of vesicle-like structures. To avoid the formation of the vesicle-like structure materials, the PS was switched from a negative charge to a positive charge through surface modification with PD （poly（diallyl-dimethyl ammonium chloride））, so that PS spheres carded the same kind of charge as the Al2O3 colloidal particles. The SEM images showed that the macroporous material of Al2O3, prepared using the modified PS spheres as templates, was free from the vesicle-like structure and voids left by the templates were connected through some windows.

关 键 词：大孔Al2O3材料 模板法 PS微球 铝溶胶 电性改性 

分 类 号：O614.31[理学—无机化学]