Observation of Binding and Rotation of Methane and Hydrogen within a Functional Metal-Organic Framework

Mathew Savage (1) , Ivan da Silva (2) , Mark Johnson (3) , Joseph H. Carter (4) , Ruth Newby (4) , Mikhail Suyetin (5, 4) , Elena Besley (4) , Pascal Manuel (2) , Svemir Rudic (2) , Andrew N. Fitch (6) , Claire Murray (7) , William I. F. David (2) , Sihai Yang (1) , Martin Schroder (1)

1 School of Chemistry [Manchester]
2 ISIS Facility
3 ILL - Institut Laue-Langevin
4 UON - University of Nottingham, UK
5 King Abdullah Univ Sci & Technol, Phys Sci & Engn Div, Thuwal 23955, Makkah, Saudi Arabia
6 ESRF - European Synchrotron Radiation Facility
7 DIAMOND Light source

The key requirement for a portable store of natural gas is to maximize the amount of gas within the smallest possible space. The packing of methane (CH4) in a given storage medium at the highest possible density is, therefore, a highly desirable but challenging target. We report a microporous hydroxyl-decorated material, MFM-300(In) (MFM = Manchester Framework Material, replacing the NOTT designation), which displays a high volumetric uptake of 202 v/v at 298 K and 35 bar for CH4 and 488 v/v at 77 K and 20 bar for H-2. Direct observation and quantification of the location, binding, and rotational modes of adsorbed CH4 and H-2 molecules within this host have been achieved, using neutron diffraction and inelastic neutron scattering experiments, coupled with density functional theory (DFT) modeling. These complementary techniques reveal a very efficient packing of H-2 and CH4 molecules within MFM-300(In), reminiscent of the condensed gas in pure component crystalline solids. We also report here, for the first time, the experimental observation of a direct binding interaction between adsorbed CH4 molecules and the hydroxyl groups within the pore of a material. This is different from the arrangement found in CH4/water clathrates, the CH4 store of nature

Domaines: Chimie

Mathew Savage, Ivan da Silva, Mark Johnson, Joseph H. Carter, Ruth Newby, et al.. Observation of Binding and Rotation of Methane and Hydrogen within a Functional Metal-Organic Framework. Journal of the American Chemical Society, 2016, 138 (29), pp.9119-9127. ⟨10.1021/jacs.6b01323⟩. ⟨hal-01573039⟩