Ultrathin graphene oxide membranes for water purification

Recently, the lack of clean and safe drinking water is huge challenge because of rapid population growth, severe droughts and environmental pollution. Two-dimensional Graphene oxide (GO) membrane with their ultrafast permanence, outstanding mechanical properties, high chemical stability is increasingly emerging as promising candidate for water purification process. But GO-based water purification technology still needs further investigation and optimization. Here, we fabricated ultrathin graphene oxide membrane by the vacuum filtration method, and successfully applied for the water purification. GO membranes with several tenth nm thickness prepared show well stacked layer structure, as characterized by atomic force microscopy and scanning electron microscopy. We have tried pressure-driven filtration to examine water flux, retention and rejection ability of the GO membranes in water purification process. The ultrathin graphene oxide membrane showed high retention and rejection rates for the charged dyes and moderate results for noncharged organic dye.