HIGHLY STABLE GRAPHENE OXIDE COMPOSITE MEMBRANES IN AN AQUEOUS ENVIRONMENT: MOLECULAR INSIGHTS
Carbon-based membranes are considered promising alternatives to membrane materials currently applied in water treatment and nanofiltration technology1. Graphene Oxide (GO) membranes are promising candidates because of their outstanding performances in selectivity and permeation. However, GO membranes need substrates to increase stability and avoid swelling or delamination2.
Molecular simulations were used to highlight the different stability of supported GO systems on three polymeric materials, the Polyvinylidene fluoride, the pristine Polyamide-imide, and the crosslinked Polyamide-imide. We monitor the position, the tilt angle, and the radial distribution function of the individual GO nanosheets to the plane of the supports. Also, we record the density profiles of the water molecules across the distance from the layers to the polymer and discuss the hydrogen bonds between water hydrogens and the oxygen atoms of the GO functional groups. The behavior of supported GO systems was compared with graphene oxide layers in water3. The results follow similar performances of experimental results and explain the nature of this intense interaction observed.