Characterization of metal-organic frameworks by water adsorption

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

Abstract

The water physisorption properties and the water stability of the metal-organic frameworks HKUST-1 (=(Cu3(BTC)2) (BTC = benzene-1,3,5-tricarboxylate)), ZIF-8, MIL-101, MIL-100(Fe) and DUT-4 (=Al(OH)(NDC)) (NDC = naphthalene-2,6-dicarboxylate) were studied. The water physisorption isotherms were compared to nitrogen physisorption isotherms and the chemical stability after water adsorption was investigated. Water adsorption does not only provide information about specific surface area, pore size and pore volume, but can also be used to estimate hydrophobicity and stability towards moisture. Both HKUST-1 and DUT-4 turned out to be unstable in direct contact with water, whereas the MIL-materials and ZIF-8 do show stability. The highest water adsorption affinity was observed for HKUST-1. Even though unstable in liquid water, for applications in trace water removal or molecular sensing HKUST-1 is a promising material. ZIF-8 is highly inert but hydrophobic. The MIL-materials are both likely candidates for water adsorption applications, but higher concentrations of the adsorbate are needed to attain an effective adsorption. DUT-4 shows insufficient adsorption capacity, but stability at ambient conditions is given.

Details

Original languageEnglish
Pages (from-to)325-330
Number of pages6
JournalMicroporous and mesoporous materials
Volume120
Issue number3
Publication statusPublished - 15 Apr 2009
Peer-reviewedYes

Keywords

Keywords

  • Bridging effect, Heat of adsorption, Metal-organic framework, Pore volume, Water adsorption