A self-cleaning titanium mesh with underwater superoleophobicity for oil/water separation and aqueous pollutant degradation

Abstract Separating oil from oily water and degrading the aqueous pollutants are two significant issues of wastewater treatment. In this work, a titanium mesh coated with W, N co-doped TiO 2 nanobelts (WNTNBs) was prepared through a simple solution route, followed by a subsequent calcination. The hierarchical nanobelt structures on the mesh contributed to considerable surface roughness, resulting in the excellent superhydrophilicity and underwater superoleophobicity. The mesh could keep its wetting performance in corrosive environments such as highly saline, acidic and alkaline conditions, revealing good environmental stability. This durable mesh is efficient for separating oil from water with high separation efficiency, as well as degrading soluble dyes such as methylene blue (MB) in the water phase even under visible light irradiation. Moreover, the mesh possesses good self-cleaning property on the removal of aqueous insoluble oil on its surface in the presence of ultraviolet and visible light, making it more effective and promising in wastewater treatment.