引用本文:
【打印本页】   【HTML】   【下载PDF全文】   View/Add Comment  【EndNote】   【RefMan】   【BibTex】
←前一篇|后一篇→ 过刊浏览    高级检索
本文已被:浏览 542次   下载 1276 本文二维码信息
码上扫一扫!
分享到: 微信 更多
Influence of Water Vapor on Silica Membrane: Adsorption Properties and Percolation Effect
Chun-lin Song*,Gang Liu*
Author NameAffiliationE-mail
Chun-lin Song* Faculty of Materials and Energy, Southwest University, Chongqing 400715, ChinaInorganic Membrane Group, MESA+ Institute for Nanotechnology, Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, the Netherlands chunlinsong@swu.edu.cn 
Gang Liu* Faculty of Materials and Energy, Southwest University, Chongqing 400715, China liugang13@swu.edu.cn 
Abstract:
The influence of water vapor on silica membrane with pore size of 4 ? has been investigated in terms of adsorption properties and percolation effect at 50 and 90 oC. Two methods are employed: spectroscopic ellipsometry for water vapor adsorption and gas permeation of binary mixture of helium and H2O. The adsorption behaviors on the silica membrane comply with the first-order Langmuir isotherm. The investigation demonstrates that helium flux through the silica membrane decreases dramatically in presence of H2O molecules. The transport of gas molecules through such small pores is believed not to be continuous any more, whereas it is reasonably assumed that the gas molecules hop from one occupied site to another unoccupied one under the potential gradient. When the coverage of H2O molecules on the silica surface increases, the dramatic decrease of helium flux could be related to percolation effect, where the adsorbed H2O molecules on the silica surface block the hopping of helium molecules.
Key words:  Silica membrane, Percolation effect, Adsorption
FundProject:
水蒸气对二氧化硅膜的影响:吸附性能与渗流效应
宋春林*,刘岗*
摘要:
研究了在50和90 oC时水蒸气对孔径约为4 ?的二氧化硅膜的吸附性能和渗流效应影响,采用椭圆偏振光谱分析水蒸气的吸附性能,以及测定氦气-H2O二元混合气体的透过性能. 研究表明水蒸气在二氧化硅膜上的吸附行为符合一阶Langmuir等温线,同时,在H2O分子存在的条件下,氦气的透过率会急剧下降. 通常,在极小孔内气体分子的传输被认为是不连续的,而是在势能下从一个占有位置跳跃到另外一个空位上. 当在二氧化硅表面的H2O分子覆盖率上升时,氦气的透过率急剧下降可能与渗流效应有关,其中吸附在二氧化硅表面的H2O分子阻碍了氦气分子的跳跃.
关键词:  二氧化硅膜,渗流效应,吸附
DOI:10.1063/1674-0068/28/cjcp1412221
分类号: