Anomalous transport in angstrom-sized membranes with exceptional water flow rates and dye/salt rejections

Enhanced Mono/Divalent Ion Separation via Charged Interlayer Channels in Montmorillonite-Based Membranes

“…To enhance the monovalent permselectivity of membranes, existing studies focus on surface modification based on the size sieving effect and electrostatic repulsion effect. − Present surface-modified membranes exhibit defects, such as non-continuity of ion channels, uncontrollability of channel sizes, and high impedance for ion transport. − Although the monovalent permselectivity of modified membranes is enhanced, the inevitable decrease of ion flux still restricts their industry application . In recent years, two-dimensional (2D) material membranes were found with excellent mass transport properties, such as ultrafast water transport property and selective ion transport property. − 2D nanomaterial membranes consist of nanoscale interlayer channels and sub-micrometer cross-layer channels. The domain-limiting effect of interlayer channels promises the ability of a 2D nanomaterial membrane to control the internal transport rates of ions with different sizes and charges by their interlayer distance and surface properties, such as surface charge density and polarity. − The sub-micrometer cross-layer channels could further amplify the domain-limiting effect.…”