Berlin 2018 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

O: Fachverband Oberflächenphysik

O 59: Nanostructures at surfaces: 1D and 2D structures and networks I

O 59.4: Vortrag

Mittwoch, 14. März 2018, 11:15–11:30, MA 141

Pressure-induced melting of confined ice — •Kai Sotthewes^1,2, Pantelis Bampoulis^1,3, Harold Zandvliet¹, Detlef Lohse³, and Bene Poelsema¹ — ¹Physics of Interfaces and Nanomaterials, Mesa+ Institute of Nanotechnology, University of Twente, P.O. Box 217, 7500AE Enschede, The Netherlands — ²II. Institute of Physics B and JARA-FIT, RWTH Aachen University, D-52074 Aachen, Germany — ³Physics of Fluids Group and Max Planck Center Twente, University of Twente, P.O. Box 217, 7500AE Enschede, The Netherlands

The states of aggregation of confined water are highly important and of great fundamental interest in surface chemistry, life and environmental sciences. Due to limited experimental access, a coherent understanding of the phase behavior and the occurring phase transitions of interfacial ice is still lacking. Using scanning probe techniques, we studied the fully reversible ice-liquid water transition for water confined between graphene and muscovite mica. A transition from two-dimensional (2D) ice into a quasi-liquid phase is observed by applying a pressure exerted by an atomic force microscopy (AFM) tip. At room temperature the critical pressure amounts to about 6 GPa. The transition is completely reversible: refreezing occurs when the applied force is lifted. The critical pressure to melt the 2D ice decreases with temperature and the latent heat of fusion is 0.15 eV/molecule, being twice as large as for bulk ice. Our findings form a paradigm of the classic phenomenon of regelation decoupled from environmental thermal effects.