Recently, a new breakthrough 12, 35, which takes advantage of superhydrophilic and underwater superoleophobic properties of a fluorodecyl POSS + x-PEGDA blend-coated hygro-responsive mesh membranes, has been first proposed by the group of A. Although superhydrophobic 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29 or superoleophobic materials 30, 31, 32, 33, 34, 35, 36 have been extensively explored, they are limited to separate immiscible oil/water mixtures and become invalid for emulsions especially in the presence of surfactant. Superwetting materials fabricated via rational combination of surface composition and rough structure have been applied to oil/water separation 11, 12, 13, 14, 15, 16. Nevertheless, due to the defects of low flux and severe fouling on account of surfactant absorption and/or pore plugging by oil droplets, the performance of filtration membranes is strictly limited and far less than application requirements 9, 10. Traditional filtration membranes such as ultrafiltration membranes have been commonly recognized as ideal materials for the separation of various emulsions including surfactant-stabilized emulsions 4, 5, 6, 7, 8. This ZnO-Co 3O 4 overlapped membrane shows great potential applications to industrial wastewater treatment, domestic sewage purification and other water remediation.Įfficient processes for oil/water separation, especially for emulsified oil/water mixtures separation are always difficult and still challenging 1, 2, 3. Fabricated by an easy and cost-efficient way, such a membrane combines the properties of under-water superoleophobicity and under-oil superhydrophobicity, which can be successfully used for the efficient separation of both surfactant-free and surfactant-stabilized emulsions, solely driven by gravity. Here we report a pure inorganic ZnO-Co 3O 4 overlapped membrane to give a brand new solution to emulsified oil/water mixture separation. There is still much deficiencies, on account of the surfactant, which could link water molecules and oil molecules to form a stabilized system. However, the separation of emulsified oil/water mixtures can be a real challenge. Materials with special wettability are developed for the separation of oil/water mixtures. The earth's environmental problems, especially for water remediation, need effective methods to solve.

Water in oil emulsion example