Capillarity-driven both light and heavy oil/water separation via combined system of opposite superwetting meshes

To better circumvent the issues of oil spills and industrial organic pollutants, it is urgent and necessary to develop advanced material or technology that can efficiently separate oil/water mixture. Herein, no matter light or heavy oil/water mixtures are separated successfully by a straight tee system combining two opposite superwetting meshes. The combined system shows a high flux (above 0.22 × 10 5  L m −2  h −1 ), high efficiency (above 99.3%) for continuous light or heavy oil/water separation with good durability. Importantly, the superhydrophilic and superhydrophobic meshes can be easily obtained via facile, viable electroless galvanic replacement reaction followed post surface modification strategy. Additionally, the capillary action was used to clarify mechanism of oil/water separation to gain insight into oil/water separation process. The merits of high flux, high efficiency, viable for light/heavy oil and durability make this separation system a powerful tool for practical application in continuous oil/water separation.