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[Display omitted] • –OH and Ag-functionalized nanosized FAU-Ag-OH zeolite was successfully synthesized. • TFN membrane with bifunctionalized FAU-Ag-OH zeolites as nanofiller was prepared. • The doping of FAU-Ag-OH zeolite resulted in a thinner PA layer with stripe morphology. • The M–0.05 membrane achieved an antibacterial efficiency of 95.4% and a FRR of 85%. • The water permeance of M–0.05 membrane with FAU-Ag-OH increased by 128%. Poor water permeance and biofouling significantly limit the application of nanofiltration (NF) membranes in wastewater treatment and seawater desalination. Herein, bifunctionalized FAU-Ag-OH zeolites, featuring abundant hydroxyl groups and silver ions on their surface, were designed and incorporated into polyamide (PA) layer of a thin-film nanocomposite (TFN) membrane, effectively enhancing the antibiofouling properties and water permeance of membrane. The plentiful hydroxyl groups and well-dispersed silver ions on the bifunctionalized FAU-Ag-OH zeolites impart the membrane with more negative surface charge, increased hydrophilicity, and superior antibiofouling property. Additionally, the doped FAU-Ag-OH zeolites can retard the diffusion of piperazine during interfacial polymerization (IP) process and have improved chemical compatibility with polymers, which results in desirable membrane structure. Consequently, the optimal M–0.05 membrane containing FAU-Ag-OH zeolites exhibited a 2.3-fold increase in water permeance (18.8 ± 2.0 L m−2 h−1 bar−1) and enhanced antibiofouling ability (with antibacterial efficiency up to 95.4 % and flux recovery ratio up to 85 %) compared with the TFC membrane. The successful fabrication of such membrane with enhanced antibiofouling properties and improved water permeance is expected to promote the application of NF membranes in water treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • High-porosity SOD/GO interlayer was used to modulate i-TFC membrane. • The SOD/GO interlayer slowed down the diffusion of the amine monomers. • The i-TFC membrane with stripe morphology and narrow pore size was prepared. • The i-TFC membrane possessed a 2.5-fold water permeance of the controlled TFC. Controllable preparation of high-performance polyamide nanofiltration (NF) membranes that can be used in various applications such as seawater desalination and wastewater treatment is very promising. In this work, a high-performance polyamide NF membrane was designed using high-porosity hydroxy sodalite/graphene oxide (SOD/GO) composite interlayer to slow down the diffusion of amine monomer and control the interfacial polymerization (IP) process. The unique tortuous effect and hydrogen bonds with amine monomers caused by the dense interlayer significantly inhibit the diffusion of amine monomers (reduction of 50 % in diffusion rate), thereby resulting in the controllable slow IP process. The slowing IP process facilitates the formation of thinner dense polyamide (PA) layer with stripe morphology and narrow pore size. Consequently, the optimal polyamide membrane with composite interlayer possesses a superior water permeability of 22.05 L m-2h−1⋅bar−1, nearly 2.5 fold that of the controlled one, while retaining an excellent rejection of Na 2 SO 4 (97.25 ± 0.81 %). Moreover, the polyamide membrane depicts outstanding antifouling propensity (flux-recovery ratio (FRR) = 82 %), long-term stability (80 h) and pressure resistance (9 bar). This work provides a novel strategy for controllable construction of high-performance NF membrane and deepens the slights into the interlayer influences IP process. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ultra-small EMT-NH 2 zeolite was used as interlayer to tailor i-TFC membrane. • EMT-NH 2 interlayer endowed the i-TFC membrane with multi-level morphology. • The i-TFC membrane exhibited 2.5-fold permeance of the TFC-control membrane. • The rejection for Na 2 SO 4 , MgSO 4 and MgCl 2 were 98.65%, 98.4% and 97.4%, respectively. • The i-TFC membrane exhibited excellent antifouling propensity (FRR = 90.1%). Conventional nanofiltration (NF) thin-film composite (TFC) membranes are strongly restricted by the trade-off between their water permeance and selectivity as well as the poor structural stability for desalination and wastewater treatment. Herein, we report an interlayer-based thin-film composite (i-TFC) NF membrane with high performance using amino-functionalized EMT zeolite (EMT-NH 2) nanocrystals as the interlayer. By adjusting the distribution density of EMT-NH 2 on the substrate, a thin and dense polyamide (PA) layer with heterogeneity multi-level morphology (nanosized nodules and nanoscale stripes) can be formed and regulated. The EMT-NH 2 zeolite nanocrystals with numerous hydrophilic groups (hydroxy and amino groups) and internal cavities can provide an additional priority water channel, increase the amine monomer storage on the substrate, and slow down the diffusion of amine monomer, thereby leading to the construction of a dense PA layer with high performance. As a result, the i-TFC-15 membrane depicted a water permeability of 13.82 ± 0.47 L m-2h−1⋅bar−1 (2.5 times that of the controlled one), while maintaining an excellent retention ability for divalent salts (98.55% for Na 2 SO 4 , 98.42% for MgSO 4 and 97.40% for MgCl 2). Additionally, the rigid hydrophilic interlayer containing zeolite nanocrystals endowed the i-TFC-15 membrane with excellent pressure resistance (up to 2.4 MPa), long-term operating stability, and antifouling propensity (flux-recovery ratio, 90.1%). This work provides an approach for fabricating a novel high-performance NF membrane and deepens our understanding of the role of porous interlayer affecting the formation of the PA layer. [ABSTRACT FROM AUTHOR]