Applied Surface Science, Vol.455, 221-226, 2018
Multifunctional oil-water and immiscible organic liquid separation by micropore arrayed Ti foil
In this work a multifunctional micropore array (size from 5 to 42 mu m) was produced by using one-step femtosecond laser microdrilling for oil-water and oil-oil separation. This novel method has many advantages, such as high precision (size error is less than 1 mu m), simple operation (one step), extensible function (even complex microstructures) just to name a few. The prepared foil exhibited superhydrophilic and underwater superoleophobic properties, which can be used to separate the light oil (C8H18) and water mixtures. After heating in dark environment 0.5 h, the prepared foil showed superhydrophobic and underwater superoleophilic properties, and can be used to separate the heavy oil (C2H4Cl2) and water mixtures. In addition, the heated sample also showed robust ability to separate the immiscible organic liquid mixtures (formamide and C2H4Cl2), exhibiting multifunctional applications. Interestingly, the heated samples would recover its original superhydrophilicity after UV irradiation in ethanol for 1 h. The samples don't contain any fluorinated compounds and display environmental stability even after sonic cleaning and scratch. This work will provide a new insight into the design of intelligent devices for oil/water mixtures separation, organic liquid mixtures separation, and water droplet manipulation.