Superhydrophilic anti-corrosive and superhydrophobic durable TiO2/Ti mesh for oil/water separation

The effective oil/water separation is important in the treatment of oily wastewater. Recently, materials with superwetting have become research hotspots due to their high oil/water separation efficiency and wide application. Here, TiO2/Ti mesh with both superhydrophilicity and superhydrophobicity was successfully fabricated to separate oil/water mixtures. Superhydrophilic TiO2 nanotube film was prepared on Ti mesh by anodic oxidation. The superhydrophilic TiO2/Ti mesh showed good oil/water separation property for various oil/water mixtures. Besides, the superhydrophilic TiO2/Ti mesh exhibited anti-corrosive separation property that had high separation efficiency for oil/strong acid/alkali/salt solution mixtures. After surface modification with lauric acid, the superhydrophilic TiO2/Ti mesh converted to superhydrophobic. The superhydrophobic TiO2/Ti mesh indicated good durability under different conditions that it showed thermal stability under 150°C, anti-icing property at -20°C and mechanical stability under abrasion and bending test. Moreover, the superhydrophobic TiO2/Ti mesh could also separate various oil/water mixtures efficiently.