Motion of water monomers reveals a kinetic barrier to ice nucleation on graphene

Abstract

The interfacial behaviour of water remains a central question to fields as diverse as protein folding, friction and ice formation[1,2]. While the structural and dynamical properties of water at interfaces differ strongly from those in the bulk, major gaps in our knowledge at the molecular level still prevent us from understanding these ubiquitous chemical processes. Information concerning the microscopic motion of water comes mostly from computational simulation[3,4] but the dynamics of molecules, on the atomic scale, is largely unexplored by experiment. Here we present experimental results combined with ab initio calculations to provide a detailed insight into the behaviour of water monomers on a graphene surface. We show that motion occurs by activated hopping on the graphene lattice. The dynamics of water diffusion displays remarkably strong signatures of cooperative behaviour due to repulsive forces between the monomers. The repulsive forces enhance the monomer lifetime ($t_m\approx 3$ s at $T_S=125$ K) in a $\text{free-gas}$ phase that precedes the nucleation of ice islands and, in turn, provides the opportunity for our experiments to be performed. Our results give a unique molecular perspective of barriers to ice nucleation on material surfaces, providing new routes to understand and potentially control the more general process of ice formation.

References in corpus (15)

• Crystal Nucleation in Liquids: Open Questions and Future Challenges in Molecular Dynamics Simulations
• Square ice in graphene nanocapillaries
• A molecular perspective of water at metal interfaces
• Friction of Water on Graphene and Hexagonal Boron Nitride from ab initio Methods: Very Different Slippage Despite Very Similar Interface Structures
• The Many Faces of Heterogeneous Ice Nucleation: Interplay Between Surface Morphology and Hydrophobicity
• Long-range repulsive interaction between TTF molecules on a metal surface induced by charge transfer
• Fast diffusion of water nanodroplets on graphene
• Reversible structural transformations in supercooled water from 135 to 245 K
• Scanning Tunneling Microscopy Study and Nanomanipulation of Graphene-Coated Water on Mica
• Long-Range Repulsion Between Spatially Confined van der Waals Dimers
• Motion of water monomers reveals a kinetic barrier to ice nucleation on graphene
• Ordered H2O Structures on a Weakly Interacting Surface, A Helium Diffraction Study of H2O/Au(111)
• Structure and dynamics investigations of a partially hydrogenated graphene/Ni(111) surface
• Inter-adsorbate forces and coherent scattering in helium spin-echo experiments
• Interaction between point charges, dipoles and graphene layers

Cited by in corpus (4)

• Motion of water monomers reveals a kinetic barrier to ice nucleation on graphene
• Molecular Mobility of Extraterrestrial Ices: Surface Diffusion in Astrochemistry and Planetary Science
• Evolution of ordered nanoporous phases during h-BN growth: Controlling the route from gas-phase precursor to 2D material by $\text{in-situ}$ monitoring
• Diffraction of atomic matter waves through a 2D crystal