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), H adsorbed on a well-ordered mesoporous silica forms a two-dimensional monolayer with a density more than twice that of bulk-solid H, 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.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9630099 | PMC |
| http://dx.doi.org/10.1038/s41557-022-01019-7 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
We report experimental results on the formation of microvoids in bulk sapphire produced through the single-shot illumination of the sample by near-infrared, simultaneously spatially and temporally focused (SSTF) laser beams. Compared with the cases of tightly focused femtosecond Gaussian and flattop beams, the SSTFs produce internal microvoids with significantly larger volumes and without cracks between the interaction sites, which may be beneficial for applications in volumetric data storage and for the studies of exotic, super-dense elemental phases contained in the densified shells surrounding the microvoids.
View Article and Find Full Text PDFFormation of a super-dense hydrogen monolayer on mesoporous silica.
Nat Chem
November 2022
Max Planck Institute for Intelligent Systems, Stuttgart, Germany.
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), H adsorbed on a well-ordered mesoporous silica forms a two-dimensional monolayer with a density more than twice that of bulk-solid H, rather than a bilayer.
View Article and Find Full Text PDFDevelopment of super-dense transfected cell microarrays generated by piezoelectric inkjet printing.
Lab Chip
January 2013
Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8566, Japan.
Super-dense transfected cell microarrays (TCMs) were created by a piezoelectric inkjet printer on a glass substrate that had been grafted with poly(ethylene glycol) (PEG). The micro-spots that contained plasmid and extra-cellular matrix (ECM) protein were separated from one another by a hydrophilic barrier generated by PEG. We successfully constructed the densest TCMs with spots of 50 μm in diameter and 150 μm in pitch.
View Article and Find Full Text PDFProgression of chondrogenesis in C3H10T1/2 cells is associated with prolonged and tight regulation of ERK1/2.
J Cell Biochem
April 2003
Division of Rheumatology, Department of Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA.
Close contact of mesenchymal cells in vivo and also in super dense micromass cultures in vitro results in cellular condensation and alteration of existing cellular signaling required for initiation and progression of chondrogenesis. To investigate chondrogenesis related changes in the activity of ubiquitous cell signaling mediated by mitogen-activated protein kinases (MAP kinase), we have compared the effect of cell seeding of pluripotent C3H10T1/2 mesenchymal cells as monolayers (non-chondrogenic culture) or high density micromass cultures (chondrogenic) on the regulation and phosphorylation state of extracellular signal-regulated kinase 1 and 2 (ERK1/2) and also on regulation of ERK1/2 nuclear targets, namely, activation protein-1 (AP-1) and serum response factor (SRF). Increasing cell density resulted in reduced DNA binding as well as activity of AP-1.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!