Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
CPP: Fachverband Chemische Physik und Polymerphysik
CPP 46: Poster II
CPP 46.5: Poster
Donnerstag, 12. März 2026, 09:30–11:30, P5
The structure and orientation of ice under confinement in Periodic Mesoporous Organosilicas (PMOs) — Niels C. Gießelmann1, Philip Lenz2,3, Sophia-Marie Meinert2, Robert P.C. Bauer1,4, Nele N. Striker1, Michael Fröba2,3, and •Felix Lehmkühler1,3 — 1Deutsches Elektronen-Synchrotron DESY, Hamburg, Germany — 2Institute for Inorganic Chemistry, University of Hamburg,Germany — 3The Hamburg Center for Ultrafast Imaging, Hamburg, Germany — 4Freiberg Center for Water Research, TU Bergakademie Freiberg, Germany
We studied water in periodic mesoporous organosilicas (PMOs) with pore diameters in the range of 2-5 nm. In these materials, the molecular mobility of water is influenced by the polarity of the organic moiety. We collected and analyzed X-ray scattering data of water and ice under confinement in PMOs with varying degrees of hydrophobicity and pore diameters and at varying temperature. A decrease in the density of the confined water was observed during cooling, which was strongly dependent on the organic moiety, as well as the pore diameter. We furthermore found deviations in the lattice constants of hexagonal ice in these materials compared to bulk water. In most cases, one lattice parameter was more strongly affected. This could be caused by orientational dependencies between the ice crystal and the pore. The orientation between the hexagonal crystallites in relation to the pore axis was therefore investigated using X-ray Cross Correlation Analysis (XCCA), indicating more uniformly oriented crystallites in more hydrophilic pores.
Keywords: Water; Ice; Confinement; Porous materials; X-ray scattering