Ultrathin PolyamideMembranes with LDH Interlayersfor High-Performance Pervaporation Desalination

Abstract Membrane-based desalination is pivotal for addressing global water scarcity, with thin-film composite polyamide (PA) membranes as the industrial standard. However, thinning the PA selective layer to enhance permeability is hindered by rapid interfacial polymerization kinetics and uncontrolled monomer transport. Here, we introduce a scalable layered double hydroxide (LDH) nanosheet interlayer to precisely regulate PA formation. The LDH interlayer provides a uniform, hydrophilic platform that moderates amine diffusion via hydrogen-bonding, enabling the fabrication of an ultrathin (∼12 nm), continuous, and robust PA layer. The resulting LDH+PA membranes exhibit superior performance in both reverse osmosis and pervaporation. Notably, pervaporation desalination of 3.5 wt % NaCl achieved a water flux of 12.1 kg m–2 h–1 with a remarkable water/salt selectivity of 10362. This interlayer-mediated strategy offers a robust approach to controlling interfacial polymerization for high-efficiency desalination membranes.