TiO2/sulfonated graphene oxide/Ag nanoparticle membrane: In situ separation and photodegradation of oil/water emulsions

Water pollution has led to increased attention on wastewater treatment and renewable industries. Various materials have been developed for removing pollutants from water. However, materials capable of emulsion separation and soluble-contaminant degradation in a single step are rare. We report a TiO2/sulfonated graphene oxide/Ag nanoparticle (TSA) membrane, which possesses useful wettability and photocatalytic properties. A photocatalytic TiO2 nanorod array-based mesh with favorable wettability properties is integrated with a sulfonated graphene oxide/Ag layer, to form a bifunctional TSA membrane. The membrane exhibits excellent oil/water separation performance, and efficient photodegradation of solubilized methylene blue under ultraviolet irradiation. The membrane also exhibits excellent stability and durability, with a water contact angle of > 150 degrees, and a high separation efficiency after 10 consecutive cycles. The membrane therefore has potential in sewage and wastewater treatment.