Ultrathin Graphene Oxide-Based Nanocomposite Membranes for Water Purification.

Two-dimensional graphene oxide (GO)-based lamellar membranes have been widely developed for desalination, water purification, gas separation, and pervaporation. However, membranes with a well-organized multilayer structure and controlled pore size remain a challenge. Herein, an easy and efficient method is used to fabricate MoO 2 @GO and WO 3 @GO nanocomposite membranes with controlled structure and interlayer spacing. Such membranes show good separation for salt and heavy metal ions due to the intensive stacking interaction and electrostatic attraction. The as-prepared composite membranes showed high rejection rates (˃70%) toward small metal ions such as sodium (Na + ) and magnesium (Mg 2+ ) ions. In addition, both membranes also showed high rejection rates ˃99% for nickel (Ni 2+ ) and lead (Pb 2+ ) ions with good water permeability of 275 ± 10 L m -2 h -1 bar -1 . We believe that our fabricated membranes will have a bright future in next generation desalination and water purification membranes.