Journal
SURFACE SCIENCE
Volume 605, Issue 13-14, Pages 1257-1262Publisher
ELSEVIER SCIENCE BV
DOI: 10.1016/j.susc.2011.04.012
Keywords
Surface diffusion; Alcohols; Carbon dioxide; Nitrogen molecule; Oxygen; Water; Liquid surfaces; Solid-liquid interfaces
Categories
Funding
- Japan Society for the Promotion of Science [22540339]
- Grants-in-Aid for Scientific Research [22540339] Funding Source: KAKEN
Ask authors/readers for more resources
Interactions of simple molecules with the surface of porous silica have been investigated using time-of-flight secondary ion mass spectrometry and temperature programmed desorption. A monolayer of water diffuses into pores at temperatures higher than 110 K. Multilayers of water are also incorporated in pores via sequential surface diffusion. In contrast, a methanol monolayer tends to stay on the surface up to 150 K, and carbon dioxide diffuses into pores rather gradually. Results can be explained as the contribution of hydrogen bonds between the adsorbate-substrate and adsorbate-adsorbate interactions. The predominance of the former (latter) might be responsible for single-molecule migration of methanol and carbon-dioxide (collective diffusion of water molecules) on the surface. These molecules are entrapped at higher coordination sites in pores, as revealed from thermal desorption peaks appearing at higher temperatures than those from non-porous silica. However, no significant difference is observed in desorption kinetics of CF(2)Cl(2), Kr, CH(4), and N(2) molecules between the porous and non-porous silica substrates. (C) 2011 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available