Robust CuO micro-cone decorated membrane with superhydrophilicity applied for oil–water separation and anti-viscous-oil fouling

Abstract Oil pollution caused by oil spills and oily wastewater has become a global issue. Oil–water separation with help of membrane possessing special wettability is a significant and feasible solution. The special wettability can be achieved by many materials. However, recent researches still have several limits for practical application. Herein, we report a surface of CuO with special microstructure, which is achieved by a simple thermal oxidation treatment of the Cu micro-cone decorated membrane. In the dynamite contact angle test, the CuO micro-cone decorated membrane exhibits higher water affinity than Cu micro-cone decorated membrane and superhydrophilicity with a water contact angle of 0°. In addition, the special micro-cone structure of CuO contributes to high mechanical and thermal stability (up to 400 °C). Furthermore, the CuO micro-cone decorated membrane presents its practical applications for oil–water separation and anti-fouling property for various viscous oils. We believe this membrane with robust stability and superhydrophilicity has great potential for practical applications in oil pollutant treatment.