Design, engineering and analytical perspectives of membrane materials with smart surfaces for efficient oil/water separation

Effective separation of various oil-water emulsions using hydrophobic/oleophilic, hydrophilic/oleophobic or amphiphilic materials has gained high research interests. With the ease in handling operations and environmental friendliness, membrane technology remains the most prevalent technique to address the oil/water emulsion problems to achieve efficient separation. The exploitation of membrane-based materials with super wettability, which encompasses the theme of superhydrophobic, superoleophilic, or a combination of both, has become a more vibrant area. Herein, we reviewed smart surfaces with superhydrophobic and superhydrophilic wettability followed by chemical methods for the separation of oil-water mixtures. Various types of membranes are also presented with suitable examples. In summary, this review clarifies the recent developments in the controllable synthesis of material with the proper size, specific compositions, and surface morphology for efficient and effective oil-water separation in a sophisticated manner to avoid environmental issues.