Abstract
Adsorption on various adsorbents of hydrogen and helium at temperatures close to their boiling points shows, in some cases, unusually high monolayer capacities. The microscopic nature of these adsorbate phases at low temperatures has, however, remained challenging to characterize. Here, using high-resolution cryo-adsorption studies together with characterization by inelastic neutron scattering vibration spectroscopy, we show that, near its boiling point (~20 K), H2 adsorbed on a well-ordered mesoporous silica forms a two-dimensional monolayer with a density more than twice that of bulk-solid H2, rather than a bilayer. Theoretical studies, based on thorough first-principles calculations, rationalize the formation of such a super-dense phase. The strong compression of the hydrogen surface layer is due to the excess of surface–hydrogen attraction over intermolecular hydrogen repulsion. Use of this super-dense hydrogen monolayer on an adsorbent might be a feasible option for the storage of hydrogen near its boiling point, compared with adsorption at 77 K.
Original language | English |
---|---|
Pages (from-to) | 1319-1324 |
Number of pages | 6 |
Journal | Nature Chemistry |
Volume | 14 |
Issue number | 11 |
DOIs | |
State | Published - Nov 2022 |
Funding
D. P. Broom and H. Oh are thanked for helpful discussions. R.B.X. thanks the Max Planck Society for its economic support. R.B.X. acknowledges research funding from the Hydrogen Materials – Advanced Research Consortium (HyMARC), established as part of the Energy Materials Network under the US Department of Energy, Office of Energy Efficiency and Renewable Energy, Hydrogen and Fuel Cell Technologies Office, under contract no. DE-AC05-00OR22725. Neutron scattering experiments were performed at the VISION instrument in ORNL’s Spallation Neutron Source, IPTS-15275, supported by the Scientific User Facilities Division, Office of Basic Energy Sciences, US Department of Energy (DOE), under contract no. DE-AC0500OR22725 with UT Battelle, LLC. The computing resources were made available through the VirtuES and the ICE-MAN projects, funded by the Laboratory Directed Research and Development programme and the Compute and Data Environment for Science (CADES) at ORNL. H.S.L. and T.H. thank ZIH Dresden for providing computational facilities. The funders had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript. The views and opinions of the authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. This manuscript has been authored by UT-Battelle, LLC under contract no. DE-AC05-00OR22725 with the US Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan ( http://energy.gov/downloads/doe-public-access-plan ). D. P. Broom and H. Oh are thanked for helpful discussions. R.B.X. thanks the Max Planck Society for its economic support. R.B.X. acknowledges research funding from the Hydrogen Materials – Advanced Research Consortium (HyMARC), established as part of the Energy Materials Network under the US Department of Energy, Office of Energy Efficiency and Renewable Energy, Hydrogen and Fuel Cell Technologies Office, under contract no. DE-AC05-00OR22725. Neutron scattering experiments were performed at the VISION instrument in ORNL’s Spallation Neutron Source, IPTS-15275, supported by the Scientific User Facilities Division, Office of Basic Energy Sciences, US Department of Energy (DOE), under contract no. DE-AC0500OR22725 with UT Battelle, LLC. The computing resources were made available through the VirtuES and the ICE-MAN projects, funded by the Laboratory Directed Research and Development programme and the Compute and Data Environment for Science (CADES) at ORNL. H.S.L. and T.H. thank ZIH Dresden for providing computational facilities. The funders had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript. The views and opinions of the authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. This manuscript has been authored by UT-Battelle, LLC under contract no. DE-AC05-00OR22725 with the US Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe-public-access-plan).