Kinetic study on electro-nucleation of water in a heterogeneous propane nano-bubble system to form polycrystalline ice I c

Abstract

Elucidating the underlying mechanisms of water solidification in heterogeneous systems is crucially important for a panoply of applications; gaining such an understanding has also proven to be very challenging to the community. Indeed, one such example lies in clarifying the thermodynamics and kinetics of electro-crystallization in heterogeneous systems, such as micro- and nano-bubble systems. Here, we employ non-equilibrium molecular dynamics of water in heterogeneous environments experiencing direct contact with a propane gas phase at various temperatures in externally applied static electric fields, elucidating significant external-field effects in inducing poly-crystalline cubic-ice formation. This is in stark contrast with recent work on homogeneous cubic-ice electro-nucleation to produce largely fault-free single crystals. We explore the kinetics of heterogeneous cubic-ice electro-nucleation under different field intensities and thermal conditions and provide an overview of time-dependent dynamics of evolution of polycrystallinity.

Unraveling Adhesion Strength between Gas Hydrate and Solid Surfaces

“…In all other models containing guest molecules, the nucleation of ice becomes very rare (there are only two special cases in dozens of simulations, and the snapshots are shown in Supporting Information (SI) Figure S1), especially bearing in mind the high concentration of guest molecules; the nanobubble nature of the guests in the IML after more thorough phase segregation hindered facilitating of ice formation in these selected, rare cases. This phenomenon indicates that the guest molecules adsorbed atop the solid surface may prevent water molecules from forming an ordered structure of ice nucleus . Therefore, in this type of model, we have only observed an orderly propagation growth of hydrate structure, as shown in Figure (B–D).…”

“…This phenomenon indicates that the guest molecules adsorbed atop the solid surface may prevent water molecules from forming an ordered structure of ice nucleus. 46 Therefore, in this type of model, we have only observed an orderly propagation growth of hydrate structure, as shown in Figure 2(B−D). Now, to be sure, there are also obvious differences in the transformed IMLs in between runs, as well as between the various starting configurations.…”