CuO(CoO,MnO)/SiO_2纳米复合气凝胶的溶胶-凝胶法制备、成胶机理及表征  

STUDY ON PREPARATION,CHARACTERIZATION AND GELATION MECHANISM OF CuO(CoO,MnO)/SiO_2 NANOCOMPOSITE AEROGEL BY SOL-GEL PROCESS

作　　者：贾千一[1] 赵越卿[2] 沈毅[1] 赵海雷[3] 梁英华[4] 荣建丰[4] 

机构地区：[1]河北理工大学材料学院,唐山063009 [2]河北理工大学轻工学院,唐山063000 [3]北京科技大学无机非金属材料系,北京100083 [4]河北理工大学化工学院,唐山063009

出　　处：《中国陶瓷》2008年第9期21-23,6,共4页China Ceramics

摘　　要：采用正硅酸乙酯(tetraethyl orthosilicate,TEOS)和Cu、Co、Mn的醋酸盐溶液,通过溶胶-凝胶法、常压干燥制备了过渡金属氧化物含量高达75wt%的CuO(CoO,MnO)/SiO2纳米复合气凝胶。采用透射电镜(TEM)、傅里叶变换红外分析(FTIR)、电子散射能谱分析(EDS)和化学分析等对其微观结构、组成及成胶机理进行了探讨。结果表明:CuO(CoO,MnO)/SiO2纳米复合气凝胶的颗粒约在5～10nm,并具有SiO2气凝胶的纳米孔隙三维网络结构和高比表面积;根据过渡金属醋酸盐与TEOS比例的不同,Cu、Co和Mn能够与氧在网络结构中形成不同程度的—O—M—O—桥键连接;通过气凝胶的多孔网络分隔作用,可使更多金属氧化物CuO、CoO和MnO的纳米粒子均匀分散于CuO(CoO,MnO)/SiO2复合气凝胶或SiO2气凝胶骨架中。这种结构既有利于提高催化剂负载量,又可充分利用CuO、CoO和MnO的助催化作用。CuO（CoO,MnO）/SiO2 nanocomposite aerogels with transition metal-oxides as high as 75wt% were prepared from tetraethyl orthosilicate （TEOS） and acetate of Cu, Co and Mn via sol-gel process and ambient pressure drying technique. The microstructure, composition and gelation mechanism were analyzed by transmission electron microscope, Fourier transform infrared spectrum, electron dispersive spectrum and chemical analysis. The results show that the particle size of CuO（CoO,MnO）/SiO2 composite aerogels is in the range of 5-10nm, and nanocomposite aerogels have nano-pores and a three-dimensional network structure as well as high specific surface areas. According to different proportion between acetates of transition metals and TEOS, bridge bonds of O--M--O- in network structure can be formed in varying degrees by the chemical bonding of transition metals and oxygen. More nanoparticles of CuO, CoO and MnO are fairly well-dispersed in the skeletons of CuO（CoO,MnO）/SiO2 composite aerogels or SiO2 aerogels by the separate effect of the porous network of aerogels, This kind of structure is not only favorable to increase the loading of catalysts, but also to make full use of the effect of transition metal-oxides as catalyst accelerators.

关 键 词：纳米复合气凝胶 溶胶-凝胶法 成胶机理 表征 

分 类 号：TQ127.2[化学工程—无机化工] O484.1[理学—固体物理]