Fig. 14. Selective OWS by using the nanosecond laser-ablated brass mesh as the separating membrane. (a) Morphology of the untreated bare brass mesh. (b) Surface microstructure of the brass mesh after nanosecond laser treatment. (c) Underwater superoleophobicity of the laser-induced rough mesh. (d) Underoil superhydrophobicity of the rough mesh. (e) Separation of light oil (kerosene) and water by using the water-wetted rough mesh. (f) Separation of heavy oil (1,2-dichloroethane) and water by using the oil-wetted rough mesh. Reproduced from ref. 81 with permission from ACS, copyright 2018.