Synthesis of vertically aligned composite microcone membrane filter for water/oil separation

A simple and efficient strategy is introduced for fabricating a layer of superhydrophobic and superoleophilic membrane on the surface of porous materials by self-assembly, and it is of great interest for the new type separation of oil and water. It is realized in this study by synthesizing an array of vertically aligned composite microcones on the surface of nickel foam by microwave plasma assisted chemical vapor deposition . The hierarchical structure, high aspect ratio , and dual-scale pine tree-like nature of the microcones formed on the nickel foam, which has microscale pores, in combination with the low surface energy of carbon, amplify both the hydrophobicity and the oleophilicity of the membrane. In addition, the membrane exhibits pH-responsivity, and the controllable water permeation can be realized by simply altering the water pH. Given its extremely high hydrophobicity and oleophilicity as well as outstanding mechanical durability, the composite frame can be used as a filter to separate oil/water mixtures and as an intelligent sponge to purify oil-contaminated water with excellent separation efficiency and absorption capacity . It should also be ideal for real world use in various environmental and chemical separation processes.