Skip to content

Mechanism of CO2 capture in nanostructured sodium amide encapsulated in porous silica

Research output: Contribution to journalArticle

Original languageEnglish
Pages (from-to)227-233
Number of pages7
JournalSurface and Coatings Technology
Early online date28 Jun 2018
DateAccepted/In press - 23 Jun 2018
DateE-pub ahead of print - 28 Jun 2018
DatePublished (current) - 25 Sep 2018


In-situ inelastic neutron scattering (INS) studies of the densification of hydrogen (H2) confined in ultramicropores of different pore geometries at 77 K have provided, for the first time, information on the effects of pore geometry on H2 phase behaviour at pressures up to 10 MPa. Here we show via INS and high-pressure H2 adsorption measurement that slit-shaped pores with a pore diameter of ~0.7 nm cause increased physical constraint of the condensed H2 compared to cylindrical shaped pores, resulting in greater H2 densification. Molecular modelling indicates that the packing of H2 in carbon slit-pores is much more efficient than that in cylindrical pores, such as are found in carbon nanotubes, resulting in formation of a double-layer of immobilised H2 molecules in slit pores and pseudo-ordered packing in cylindrical pores of the same diameter. The average H2 densities in these slit pores and cylindrical pores are 70 and 50 m3g-1, respectively, calculated from the high pressure volumetric H2 isotherms at 77 K. This insight into the effects of pore geometry on confinement of molecules can be used to guide the development of new porous adsorbents tailored for maximum H2 storage capacities.

    Research areas

  • Carbon capture, Encapsulation, Porous silica, Sodium amide



  • Full-text PDF (accepted author manuscript)

    Rights statement: This is the author accepted manuscript (AAM). The final published version (version of record) is available online via Elsevier at . Please refer to any applicable terms of use of the publisher.

    Accepted author manuscript, 1 MB, PDF-document

    Embargo ends: 28/06/19

    Request copy

    Licence: CC BY-NC-ND


View research connections

Related faculties, schools or groups