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Direct Observation of Hydrogen Adsorption Sites and Nano-Cage Formation in Metal-Organic Frameworks (MOF)

T. Yildirim·M. R. Hartman
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Abstract

The hydrogen adsorption sites in MOF5 were determined using neutron powder diffraction along with first-principles calculations. The metal-oxide cluster is primarily responsible for the adsorption while the organic linker plays only a secondary role. Equally important, at low temperatures and high-concentration, H2 molecules form unique interlinked high-symmetry nano-clusters with intermolecular distances as small as 3.0 Ang. and H2-uptake as high as 10-wt%. These results hold the key to optimizing MOF materials for hydrogen storage applications and also suggest that MOFs can be used as templates to create artificial interlinked hydrogen nano-cages with novel properties.

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T. Yildirim, M. R. Hartman. 2005-07-09. Direct Observation of Hydrogen Adsorption Sites and Nano-Cage Formation in Metal-Organic Frameworks (MOF). https://doi.org/10.1103/physrevlett.95.215504

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