Journal article
Critical Factors Driving the High Volumetric Uptake of Methane in Cu-3(btc)(2)
Journal of the American Chemical Society, Vol.137(33), pp.10816-10825
08/26/2015
DOI: 10.1021/jacs.5b06657
PMID: 26263038
Abstract
A thorough experimental and computational study has been carried out to elucidate the mechanistic reasons for the high volumetric uptake of methane in the metal-organic framework Cu-3(btc)(2) (btc(3-) = 1,3,5-benzenetricarboxylate; HKUST-1). Methane adsorption data measured at several temperatures for Cu-3(btc)(2), and its isostructural analogue Cr-3(btc)(2), show that there is little difference in volumetric adsorption capacity when the metal center is changed. In situ neutron powder diffraction data obtained for both materials were used to locate four CD4 adsorption sites that fill sequentially. This data unequivocally shows that primary adsorption sites around, and within, the small octahedral cage in the structure are favored over the exposed Cu2+ or Cr2+ cations. These results are supported by an exhaustive parallel computational study, and contradict results recently reported using a time-resolved diffraction structure envelope (TRDSE) method. Moreover, the computational study reveals that strong methane binding at the open metal sites is largely due to methane-methane interactions with adjacent molecules adsorbed at the primary sites instead of an electronic interaction with the metal center. Simulated methane adsorption isotherms for Cu-3(btc)(2) are shown to exhibit excellent agreement with experimental isotherms, allowing for additional simulations that show that modifications to the metal center, ligand, or even tuning the overall binding enthalpy would not improve the working capacity for methane storage over that measured for Cu-3(btc)(2) itself.
Details
- Title: Subtitle
- Critical Factors Driving the High Volumetric Uptake of Methane in Cu-3(btc)(2)
- Creators
- Zeric Hulvey - NIST Center for Neutron ResearchBess Vlaisavljevich - Univ Calif Berkeley, Dept Chem & Biomol Engn, Berkeley, CA 94720 USAJarad A. Mason - Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USAEhud Tsivion - Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USATimothy P. Dougherty - NIST Center for Neutron ResearchEric D. Bloch - Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USAMartin Head-Gordon - Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USABerend Smit - École Polytechnique Fédérale de LausanneJeffrey R. Long - Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USACraig M. Brown - NIST Center for Neutron Research
- Resource Type
- Journal article
- Publication Details
- Journal of the American Chemical Society, Vol.137(33), pp.10816-10825
- DOI
- 10.1021/jacs.5b06657
- PMID
- 26263038
- NLM abbreviation
- J Am Chem Soc
- ISSN
- 0002-7863
- eISSN
- 1520-5126
- Publisher
- Amer Chemical Soc
- Number of pages
- 10
- Grant note
- DE-SC0001015 / U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences; United States Department of Energy (DOE) DE-FG02-12ER16362 / Nanoporous Materials Genome Center - U.S. Department of Energy, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences, and Biosciences DE-AC02-05CH11231 / Office of Science of the U.S. Department of Energy; United States Department of Energy (DOE) DMR-09414772 / NIST/NSF REU Summer Undergraduate Research Fellowship (SURF) - Center for High Resolution Neutron Scattering (CHRNS)
- Language
- English
- Date published
- 08/26/2015
- Academic Unit
- Chemistry
- Record Identifier
- 9984618641102771
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