Three-Dimensional-Nanostructured Superhydrophilic Mesh Membrane for Oil/Water Separation via a Corrosion-Mediated Self-Assembly Strategy

Abstract

Superhydrophilic surface materials featuring underwater superoleophobicity are highly useful for oil/water separation. However, the limited interfacial stability and anti-oil-fouling properties seriously hinder their practical applications. Here, a mesh membrane covered with metal phosphate nanoflowers is designed using a simple and effective in situ solution corrosion-mediated self-assembly (CMSA) strategy. This simple and rapid method uses a 10% phosphoric acid solution under controlled conditions for 6–18 h to directly generate three-dimensional (3D) nanostructures on the surface through electrochemical dissolution and regeneration. Additionally, the in situ reaction enhances the homogeneity and stability of the nanostructures on the surface, inducing excellent interfacial stability. The unique 3D nanoflower structure and phosphate groups endow the mesh membrane with excellent superwettability and oil-fouling resistance. Compared with existing technologies, this mesh membrane, benefiting from its remarkable anti-oil-fouling properties and superior stability, demonstrates enhanced performance in the continuous and long-term separation of oil from various oily wastewaters, including immiscible oil/water mixtures, oil/water emulsions, and floating oils. Its exceptional anti-oil-fouling property, high separation capacity, and excellent long-term durability highlight its practical potential for cleaning oily effluents.