Understanding the Adsorption Mechanism of Xe and Kr in a Metal-Organic Framework from X-ray Structural Analysis and First- Principles Calculations

Journal Article · Thu Apr 16 04:00:00 EDT 2015 · Journal of Physical Chemistry Letters

DOI:https://doi.org/10.1021/acs.jpclett.5b00440· OSTI ID:1241386

Ghose, Sanjit K. ^[1]; Li, Yan ^[1]; Yakovenko, Andrey ^[2]; Dooryhee, Eric ^[1]; Ehm, Lars ^[3]; Ecker, Lynne E. ^[1]; Dippel, Ann-Christin ^[4]; Halder, Gregory J. ^[2]; Strachan, Denis M. ^[5]; Thallapally, Praveen K. ^[6]

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1. Brookhaven National Lab. (BNL), Upton, NY (United States)
2. Argonne National Lab. (ANL), Argonne, IL (United States)
3. Brookhaven National Lab. (BNL), Upton, NY (United States); Stony Brook Univ., NY (United States)
4. Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
5. DM Strachan, LLC., Bend, OR (United States)
6. Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

Enhancement of adsorption capacity and separation of radioactive Xe/Kr at room temperature and above is a challenging problem. Here, we report a detailed structural refinement and analysis of the synchrotron X-ray powder diffraction data of Ni-DODBC metal organic framework with in situ Xe and Kr adsorption at room temperature and above. Our results reveal that Xe and Kr adsorb at the open metal sites, with adsorption geometries well reproduced by DFT calculations. The measured temperature-dependent adsorption capacity of Xe is substantially larger than that for Kr, indicating the selectivity of Xe over Kr and is consistent with the more negative adsorption energy (dominated by van der Waals dispersion interactions) predicted from DFT. Our results reveal critical structural and energetic information about host–guest interactions that dictate the selective adsorption mechanism of these two inert gases, providing guidance for the design and synthesis of new MOF materials for the separation of environmentally hazardous gases from nuclear reprocessing applications.

• Research Organization: Argonne National Lab. (ANL), Argonne, IL (United States)
• Sponsoring Organization: USDOE Office of Nuclear Energy; USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
• DOE Contract Number: AC02-06CH11357
• OSTI ID: 1241386
• Journal Information: Journal of Physical Chemistry Letters, Journal Name: Journal of Physical Chemistry Letters Journal Issue: 10 Vol. 6; ISSN 1948-7185
• Publisher: American Chemical Society
• Country of Publication: United States
• Language: English

Related Subjects

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
X-ray diffraction
density functional calculations
metal-organic frameworks
noble gases
vad der Waals interactions