Superhydrophilic and underwater superoleophobic in-situ derived 2D Ni-Fe MOF/HNTs composite-enhanced polyvinyl alcohol (PVA) hydrogel membrane for gravity-driven oil/water separation

In this work, we successfully prepared the 2D Ni-Fe MOF-HNTs composites by in-situ hydrothermal growth, followed by enabling it to full into PVA hydrogels, thereupon fabricating the oil/water separation 2D Ni-Fe MOF-HNTs/PVA-decorated stainless steel mesh. The structures and mechanical properties of the composites were identified by a series of characterizations. The results showed that the 2D Ni-Fe MOF nanosheets were gown on the outer surface of HNTs to form the exclusive composite structure and the 2D Ni-Fe MOF-HNTs/PVA composite membrane possessed a more compact pore structure, which exhibited the outstanding mechanical performance and the fatigue resistance ability. The surface property characterizations demonstrated that the 2D Ni-Fe-MOF-HNTs/PVA composite membrane had the superhydrophilic and underwater superoleophobic features. Ultimately, the results of the water flux and separation efficiency on 2D Ni-Fe-MOF-HNTs/PVA composite membrane for oil-water separation and emulsion separation corroborated that it was a promising high-performance separation composite membrane.