Crystallisation of ice in charged Pt nanochannel

Using molecular dynamics simulations, we examine the crystallisation process of the extended simple point charge model (SPC/E) water confined in a charged Pt nanochannel. The presence of the external electric field enhances the surface layering of water and promotes the super-cooled water to crystallise into Ic ice within tens of nanoseconds. Ic ice is found to nucleate from the interior of the water lamina, and the Pt(111) surfaces do not show a remarkable promotion of Ic ice nucleation. Structural analysis reveals that a two-dimensional hydrogen-bond network is built among the water molecules absorbed on the charged Pt surfaces, which influences the bonding of the molecules between the first and the second layers, and disturbs the formation of tetrahedral structures that match Ic ice, finally resulting in the nucleation-free near the walls. Such arrangements of water molecules remain in the subsequent growth of Ic ice and cause the slowdown of growth velocity while approaching surfaces.