Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Enhancement of Hydrogen Storage Capacity in Hydrate Lattices

Journal Article · · Chemical Physics Letters
First principles electronic structure calculations of the gas phase pentagonal dodecahedron (H2O)20 (D-cage) and tetrakaidecahedron (H2O)24 (T-cage), which are building blocks of structure I (sI) hydrate lattice, suggest that these can accommodate up to a maximum of 5 and 7 guest hydrogen molecules, respectively. For the pure hydrogen hydrate, Born-Oppenheimer Molecular Dynamics (BOMD) simulations of periodic (sI) hydrate lattices indicate that the guest molecules are released into the vapor phase via the hexagonal phases of the larger T-cages. An additional mechanism for the migration between neighboring D- and T-cages was found to occur through a shared pentagonal face via the breaking and reforming of a hydrogen bond. This molecular mechanism is also found for the expulsion of a CH4 molecule from the D-cage. The presence of methane in the larger T-cages was found to block this release, therefore suggesting possible scenarios for the stabilization of these mixed guest clathrate hydrates and the potential enhancement of their hydrogen storage capacity.
Research Organization:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US)
Sponsoring Organization:
USDOE
DOE Contract Number:
AC05-76RL01830
OSTI ID:
1035731
Report Number(s):
PNNL-SA-83751; KC0301020
Journal Information:
Chemical Physics Letters, Journal Name: Chemical Physics Letters Vol. 525-526; ISSN CHPLBC; ISSN 0009-2614
Country of Publication:
United States
Language:
English

Similar Records

Low-energy networks of the T-cage (H2O)(24) cluster and their use in constructing periodic unit cells of the structure I (sl) hydrate lattice
Journal Article · Wed Jun 10 00:00:00 EDT 2009 · Journal of the American Chemical Society, 131(22):7564-7566 · OSTI ID:958487

Structures, Energetics and Spectroscopic Fingerprints of Water Clusters n=2-24
Book · Thu Jun 08 00:00:00 EDT 2017 · OSTI ID:1364012

Guest-Host Interactions in Clathrate Hydrates: Benchmark MP2 and CCSD(T)/CBS Binding Energies of CH4, CO2 and H2S in (H2O)20 Cages
Journal Article · Thu Aug 12 00:00:00 EDT 2021 · The Journal of Physical Chemistry Letters · OSTI ID:1823097