Facile preparation of grass-like structured NiCo-LDH/PVDF composite membrane for efficient oil–water emulsion separation

Development of antifouling membrane to separate oil–water emulsions by low energy consumption approach is an urgent demand. Herein, we report for the first time a grass-like structured composite membrane from array growth of nickel cobalt layered double hydroxide (NiCo-LDH) onto the polydopamine modified polyvinylidene fluoride (PVDF) membrane surface via simple hydrothermal strategy. The surface morphology of as-prepared membrane has controlled by hydrothermal time. The obtained NiCo-LDH/PVDF composite membrane exhibits superhydrophilicity/underwater superoleophobicity for separating both surfactant-free and surfactant-stabilized oil–water emulsions by capillary effect under the driving of gravity. Moreover, with the advantages of antifouling performance, the membrane displays outstanding cyclic performance for long-term application, which is promising for practical oily wastewater treatment.