Crystal-size effect on the kinetics of CO2 adsorption in metal organic frameworks studied by NMR
Weiming Jiang1, Kazuyuki Takeda1
1Division of Chemistry, Graduate School of Science, Kyoto University, 606-8502 Kyoto, Japan. takezo@kuchem.kyoto-u.ac.jp.
Abstract:
We study the dynamics and the exchange of carbon dioxide (CO2) adsorbed in a metal organic framework (MOF) by 13C NMR for various sizes of the host crystal ranging from micrometers to millimeters. We found that the guest CO2 molecules adsorbed in [Zn2(1,4-NDC)2(dabco)]n MOF undergo exchange at a rate that depends on the size of the host crystal, revealing that the smaller the host crystals are, the faster the exchange becomes. Such a trend can be explained by the size-dependent surface-to-volume ratio.
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