• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Nanotechnology >Gas adsorption and capillary condensation in nanoporous alumina films
【24h】

Gas adsorption and capillary condensation in nanoporous alumina films

机译：纳米多孔氧化铝膜中的气体吸附和毛细管冷凝

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Gas adsorption and capillary condensation of organic vapors are studied by optical interferometry, using anodized nanoporous alumina films with controlled geometry (cylindrical pores with diameters in the range of 10 - 60 nm). The optical response of the film is optimized with respect to the geometric parameters of the pores, for potential performance as a gas sensor device. The average thickness of the adsorbed film at low relative pressures is not affected by the pore size. Capillary evaporation of the liquid from the nanopores occurs at the liquid - vapor equilibrium described by the classical Kelvin equation with a hemispherical meniscus. Due to the almost complete wetting, we can quantitatively describe the condensation for isopropanol using the Cohan model with a cylindrical meniscus in the Kelvin equation. This model describes the observed hysteresis and allows us to use the adsorption branch of the isotherm to calculate the pore size distribution of the sample in good agreement with independent structural measurements. The condensation for toluene lacks reproducibility due to incomplete surface wetting. This exemplifies the relevant role of the fluid - solid (van der Waals) interactions in the hysteretic behavior of capillary condensation.
机译：使用具有受控几何形状（直径在10-60 nm范围内的圆柱孔）的阳极氧化纳米多孔氧化铝膜，通过光学干涉法研究了有机蒸气的气体吸附和毛细管冷凝。膜的光学响应相对于孔的几何参数被优化，以作为气体传感器装置的潜在性能。低相对压力下吸附膜的平均厚度不受孔径的影响。液体从纳米孔的毛细管蒸发发生在具有半球形弯月面的经典开尔文方程描述的液-气平衡下。由于几乎完全润湿，我们可以使用开氏方程中带有圆柱弯月面的Cohan模型来定量描述异丙醇的缩合。该模型描述了观察到的磁滞现象，并允许我们使用等温线的吸附分支来计算样品的孔径分布，与独立的结构测量结果非常吻合。由于表面润湿不完全，甲苯的缩合反应缺乏重现性。这例证了流体-固体（范德华）相互作用在毛细管冷凝的滞后行为中的相关作用。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号