Thin-Film Composite Membranes Interlayered with Amphiphilic MoS2 Nanosheets via Controllable Interfacial Polymerization for Enhanced Desalination Performance

Polyamide (PA)-based nanofiltration (NF) membranes have demonstrated extensive applications for a sustainable water-energy-environment nexus. A rational control of interfacial polymerization (IP) is highly efficacious to enhance NF separation performance yet remains a technical challenge. Herein, we proposed a regulation strategy of constructing amphiphilic molybdenum disulfide/cetyltrimethylammonium bromide interlayer atop the Kevlar hydrogel substrate. The amphiphilic nanosheet interlayered NF membrane exhibited a crumpled PA surface with an elevated cross-linking degree of 76.9%, leading to an excellent water permeance (16.8 L m^-2 h^-1 bar^-1) and an impressive Na₂SO₄ rejection (99.1%). Meanwhile, the selectivity coefficient of Na₂SO₄/NaCl of the optimized TFC membrane reached 91, surpassing those of the recently reported NF membranes. Moreover, the optimized membrane exhibited a desirable rejection of over 90% against Mn²⁺ and Cu²⁺ in actual textile wastewater. Importantly, the underlying NF membrane formation mechanism was elucidated via both experiments and molecular simulations. The synchronous control of mass and heat transfer of IP process offers a new methodology for the state-of-the-art membrane fabrication, which opens more avenues in softening of brackish water and purification of industrial wastewater containing heavy metal ions.