Superflexible/superhydrophilic PVDF-HFP/CuO-nanosheet nanofibrous membrane for efficient microfiltration

Membrane fouling and poor flexibility plague membrane technology for further application in water treatment. Herein, we introduce a hierarchical superflexible/superhydrophilic poly (vinylidene fluoride-co-hexa-fluoropropylene) (PVDF-HFP)/CuO-nanosheet membrane, which is capable of separating Polystyrene (PS) microspheres (diameter large than 300 nm) with high separation efficiency (higher than 99.89%). Moreover, the resulting membrane maintained 98.10% water flux after 60 min, suggesting excellent anti-fouling property. The anti-fouling property is contributed by the membrane superhydrophilicity, a result of the extreme roughness of CuO-nanosheet and the hydrophilic nature of CuO. Furthermore, the membrane processes outstanding flexibility due to the PVDF-HFP nanofiber backbone, which widens its applicability in practical industrial employment. Therefore, such a membrane with anti-fouling, high separation efficiency, super flexibility, as well as acceptable water flux (2360 ± 50 Lm− 2h− 1, 0.3 bar) and good mechanical properties (stress at break 6.65 MPa and elongation at break 67.35%), makes the membrane a good candidate for practical water microfiltration.