Electro-assisted interfacial growth of biomimetic KFUPM-100 MOF membrane for ultrafast oil-water separation with breakthrough stability

In membrane-based oil–water separation, the use of advanced materials is limited by low permeability and rapid fouling. Thus, there is an increasing focus on designing super-wettable materials for effective oily wastewater treatment. Metal-organic frameworks (MOFs) have recently gained attention in separation technologies, but their use in oil–water separation is limited due to challenges in creating hydrolytically stable MOFs and forming a durable thin layer on supports. For the first time, this study introduces KFUPM-100, a water-stable MOF with pivalic acid and adenine as ligands and Cu as the metal node. The KFUPM-100 MOF was grown on a Cu-mesh using an electro-assisted method and exhibits superhydrophilicity and underwater superoleophobicity, ideal for oil–water separation. KFUPM-100@Cu-mesh membrane demonstrated superior stability, as shown by BET surface area, contact angle, and molecular dynamic simulations. It achieved nearly complete oil rejection (>99 %) at a permeate flux of 47,808 to 49,300 L/m² h, outperforming previously reported oil separation membranes. Remarkably, KFUPM-100 membrane maintained its performance even after 10 months in water and under both acidic and basic conditions for 14 cycles. This work advances the design of hydrolytically stable MOF-based membranes by controlling the host surface and adding a sterically hindered co-ligand, opening new opportunities for water applications.