Multilayer Two-Dimensional Water Structure Confined in MoS 2

The conflicting interpretations (square vs rhomboidal) of the recent experimental visualization of the two-dimensional (2D) water confined in between two graphene sheets by transmission electron microscopy measurements, make it important to clarify how the structure of two-dimensional water depends on the constraining medium. Toward this end, we report here molecular dynamics (MD) simulations to characterize the structure of water confined in between two MoS 2 sheets. Unlike graphene, water spontaneously fills the region sandwiched by two MoS 2 sheets in ambient conditions to form planar multilayered water structures with up to four layer. These 2D water molecules form a specific pattern in which the square ring structure is formed by four diamonds via H-bonds, while each diamond shares a corner in a perpendicular manner, yielding an intriguing isogonal tiling structure. Comparison of th…