Superlyophobic anti-corrosive and self-cleaning titania robust mesh membrane with enhanced oil/water separation

Abstract

Abstract Oil/water separation becomes a research hotspot because of the frequent oil spill accidents. Although lots of separating membranes with super-wettability have been fabricated to separate oil or water from the mixtures, to separate both heavy (ρ oil > ρ water ) and light (ρ oil water ) oil/water mixtures with high efficiency and high flux is still a challenge, especially to obtain a membrane with mechanically robust nanostructures, and simultaneously anti-corrosive and self-cleaning ability. Herein, a novel titania nanostructured mesh membrane with superamphiphilicity in air, and dual superlyophobicity in liquid mediums were fabricated. Both high separation efficiency and flux of more than 99.2% and 16,954 L m −2 h −1 were obtained for both light and heavy oil/water mixtures. Importantly, the TiO 2 mesh membrane showed mechanically robust nanostructures and anti-corrosive ability, which can remain dual superlyophobicity, i.e., both underwater superoleophobicity and underoil superhydrophobicity and high oil-water separating behavior even after immersion in solutions of strong acid, basic, high salty, various organic solvents, and even after being abrased and adhered by pure sands and adhesive tape, respectively. Meanwhile, TiO 2 mesh membrane had shown photocatalytic decomposition of oil and organic molecules under UV irradiation, demonstrating unique self-cleaning and anti-fouling ability of the membranes. Given so many merits of these unique membranes, it is believed to these membranes have great potentials to be used in wastewater treatment and oil spill recovery.