纳米多孔SiO_2气凝胶的表面修饰和吸附特性(英文)  

Surface Modification and Adsorption Properties of SiO_2 Nanoporous Aerogels

作　　者：倪星元[1] 李洋[1] 张志华[1] 沈军[1] 周斌[1] 吴广明[1] 

机构地区：[1]同济大学波耳固体物理研究所,上海200092

出　　处：《稀有金属材料与工程》2010年第S2期22-25,共4页Rare Metal Materials and Engineering

基　　金：National Natural Science Foundation of China (20133040);Chinese National Foundation of High Technology (2002AA842052);Shanghai Nanotechnology Promotion Center (0352nm056, 0452nm088);Shanghai Key Subject Program and Trans-Century Training Program Foundation for the Talents by the State Education Commission (05QMH1413)

摘　　要：采用溶胶-凝胶法,通过表面修饰等工艺,在常压条件下制备出高气孔率的疏水性 SiO2气凝胶。表面修饰能够调节气凝胶内部纳米多孔结构和增大比表面积。表面修饰采用三甲基氯硅烷,其 Si-CH3基团能取代原有气凝胶表面的 O-H 基团,使其具有疏水特性。用扫描电镜,红外光谱以及孔径分布仪对其结构和表面基团进行了表征,对其吸附特性进行了测试。结果表明,SiO2 气凝胶具有纳米多孔结构,且有较好的疏水特性,其吸附性能较活性炭纤维和活性炭颗粒高 3～4 倍,再吸附容量基本不变,是一种极好的高吸附材料,具有广阔应用前景。SiO2 aerogels were prepared via sol-gel process and dried at ambient pressure. Surface modification was employed to adjust the nanoporous structure and to increase the surface area in the aerogels. The hydrophobic Si-CH3 groups of trimethylchlorosilane (TMCS) replaced the hydrophilic-OH groups on the surface of aerogels. The infrared spectrum (IR) revealed differences between groups on the surface as a result of the surface modification. The contact angle between the silica aerogels and water was 130°, indicating excellent hydrophilic property of the silica aerogels. A novel application of SiO2 aerogels is in the area of adsorption with super surface area and high porosities. The experiments suggested that the adsorption capacity of silica aerogels for methylbenzene, carbon tetrachloride, and acetaldehyde was 3-4 times of that of activated carbon fiber (ACF) or granule of activated carbon (GAC).

关 键 词：吸附特性 表面修饰 SIO2气凝胶 纳米多孔 

分 类 号：TB383.1[一般工业技术—材料科学与工程]