jz9b02774_si_003.mp4 (10.97 MB)
Water Diffusion in Wiggling Graphene Membranes
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posted on 2019-11-11, 18:08 authored by Wei Cao, Jin Wang, Ming MaWater diffusion in
nanopores has attracted considerable attention
in the past decades. Recently the coupling between the vibration of
pore walls and movement of confined water has been recognized to largely
enhance diffusion. However, its impact on water diffusion in graphene
oxide membranes remains to be discussed. Here we explore how water
diffusion couples with the thermal fluctuation of graphene nanochannels
by molecular dynamics simulations. Our finding demonstrates an approximately
linear dependence of diffusion enhancement on temperature; i.e., the
wiggling nanopore enhances diffusion at low temperature and inhibits
diffusion at high temperature. This mechanism is further extended
to be applicable for another two typical layered materials, hBN and
MoS2. These results offer opportunities to tune surface
diffusion by thermal operation or mechanical activation, advancing
the application of two-dimensional materials in membrane separations.