Novel thin-film composite membrane with polydopamine-modified polyethylene support and tannic acid-Fe3+ interlayer for forward osmosis applications

Polyethylene (PE) has recently gained attention as an advantageous support material in forward osmosis (FO) owing to its low structural parameters. A novel thin-film composite (TFC) membrane for FO was fabricated by introducing a tannic acid (TA)-Fe3+ interlayer on polydopamine (PDA)-modified PE via interfacial polymerization. The TA-Fe3+ influenced the diffusion of m-phenylenediamine, causing unique worm-like morphology polyamide (PA) layer, distinct from traditional “ridge and valley” morphology. Worm-like structures provided more permeation sites improved water flux (71.2 L?m?2?h?1). Furthermore, prevented some salt molecules passing through resulted specific (0.03 g?L?1). key overcoming trade-off between permeability selectivity. It functioned bridge connecting PA layer PDA-modified chemical bonding, adhesion strength enhanced. This excellent stability obtained TFC membrane. study presents new method design with perm-selectivity manipulatable morphologies applications.