Water Cluster Growth in Hydrophobic Solid Nanospaces

✍ Scribed by Tomonori Ohba; Hirofumi Kanoh; Katsumi Kaneko

• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 170 KB
• Volume: 11
• Category: Article
• ISSN: 0947-6539
• DOI: 10.1002/chem.200400918

✦ Synopsis

Abstract

The growth mechanism of water clusters in carbon nanopores is clearly elucidated by in situ small‐angle X‐ray scattering (SAXS) studies and grand canonical Monte Carlo (GCMC) simulations at 293–313 K. Water molecules are isolated from each other in hydrophobic nanopores below relative pressures (P/P~0~) of 0.5. Water molecules associate with each other to form clusters of about 0.6 nm in size at P/P~0~=0.6, accompanied by a remarkable aggregation of these clusters. The complete filling of carbon nanopores finishes at about P/P~0~=0.8. The correlation length analysis of SAXS profiles leads to the proposal of a growth mechanism for these water clusters and the presence of the critical cluster size of 0.6 nm leads to extremely stable clusters of water molecules in hydrophobic nanopores. Once a cluster of the critical size is formed in hydrophobic nanopores, the predominant water adsorption begins to fill carbon nanopores.