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Constructing a functional layer on the surface of commercial membrane (as a substrate) to inhibit the formation of biofilms is an efficient strategy to prepare an antibacterial anion exchange membrane (AEM). Herein, a rechargeable multifunctional anti‐biological system is reported by utilizing the mussel‐inspired L‐dopa connection function on commercial AEMs. Cobalt nanoparticles (Co NPs) and N‐chloramine compounds are deposited on the AEM surface by a two‐step modification procedure. The anti‐biofouling abilities of the membranes are qualitatively and quantitatively analyzed by adopting common Gram‐negative (E. coli) and Gram‐positive (S. aureus & Bacillus) bacteria as model biofouling organisms. The optimized membrane exhibits a high stability concerning the NaCl solution separation performance within 240 min. Meantime, the mechanism of the anti‐adhesion is un‐veiled at an atomic level and molecular dynamics (MD) simulation are conducted to measure the interaction, adsorption energy and average loading by using lipopolysaccharide (LPS) of E. coli. In view of the superior performance of antibacterial surfaces, it is believed that this work could provide a valuable guideline for the design of membrane materials with resistance to biological contamination. [ABSTRACT FROM AUTHOR]

[Display omitted] • A kind of organic solvent resistant and monovalent anions selective AEMs has been prepared. • The optimized AEM shows a low swelling ratio of 4.39% in DMSO at room temperature. • The perm-selectivity (Cl−/SO 4 2−) of AEM could reach 29.4 in a mixed solution containing DMSO. • The performance of AEM improves after protonation of PEI under acidic conditions. Solvent-resistant anion exchange membranes (AEMs) with a microphase separation structure have demonstrated the potential for efficient separation of monovalent and multivalent ions and solvent recovery. In this work, a kind of imidazole side-chain AEM based on poly(2,6-dimethyl-1,4-phenylene oxide) (BPPO) and crosslinking agent polyethyleneimine (PEI) was synthesized to achieve efficient separation of Cl− and SO 4 2− ions through electrodialysis (ED) in organic solvent systems. The as-prepared AEMs exhibit favorable dimensional stability in various organic solvents, such as 60 % DMSO (aq.), 60 % DMF (aq.), 60 % ethanol (aq.), and display outstanding ion separation performance for Cl−/SO 4 2− ions during the ED process. Specifically, the swelling ratio of the AEM in the organic solvents remains < 5.5 % for the AEM with a grafting rate of 60 % of 1-butylimidazole (BIm) on BPPO benzyl bromide groups. At a current density of 2.5 mA·cm−2 during the ED process, the perm-selectivity of Cl−/SO 4 2− ions can reach 72.1. Importantly, even in a mixed solution containing 10 % organic solvent and 0.5 M NaCl and Na 2 SO 4 (aq.), the perm-selectivity of Cl−/SO 4 2− ions could still remain at 29.4. This achievement can be attributed to the integration of BIm and PEI, which forms stable sub-nanometer ion channels within the AEMs, enabling selective separation of ions of different sizes in organic solvent systems. [ABSTRACT FROM AUTHOR]

A series of gentamicin‐modified anion exchange membranes (AEMs) immobilized by mussel‐inspired dopamine coating is prepared in this work. The purpose is to improve antibacterial activity and fouling resistance of the commercial AEMs (AEM Type I, Fujifilm Co.). As a result of the applied modification, the hydrophilicity of membrane surface improved significantly. Thus, the as‐prepared modified AEMs exhibit the good antifouling property, in electrodialysis (ED) experiments by using the sodium dodecylbenzenesulfonate and albumin from bovine serum as model foulants. Furthermore, taking into account the results of the antibacterial test, the resulting modified AEMs exhibit improved antibacterial property for Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). After a brief contact with bacteria, the antibacterial rates of modified AEMs coating with gentamicin‐based polymer are 80.11% for E. coli and 90.66% for S. aureus, which are much higher than pristine AEM (6.28% and 9.07%), respectively. In addition, the modified membrane has good operational stability during ED process and recovery ability after contamination, and also maintains satisfactory electrochemical properties. This investigation highlights a design of simple strategy for the preparation of antimicrobial and antifouling AEM, which can be used for ED. [ABSTRACT FROM AUTHOR]

Surface modification is a critical method for fabricating novel anion exchange membranes (AEMs) with high monovalent anion selectivity and desired antifouling property. In this work, we have modified a commercial AEM with “sandwich”-like structure, composed of upper/bottom bilayers of polydopamine (PDA) and sandwich alternating bilayers of poly (sodium 4-styrene sulfonate) (PSS)/hydroxypropyltrimethyl ammonium chloride chitosan-nano silver particles (HACC-Ag Np), aiming to enhance the monovalent selectivity and fouling resistant for electrodialysis (ED) application. Our investigations suggest that the permselectivity ( P S O 4 2 − C l − ) of the modified AEM with 4.5 bilayers of PSS can reach 5.1, significantly outperforming that of commercial standard AEM (0.98). Due to the electrostatic repulsion resulted from the negatively charged top layer in sandwich structure and hydrophilia of PDA, the time elapsed until the occurrence of fouling (transition time) of the modified AEM (125 min) is much longer than that of the original one (60 min). In addition, anchored silver nanoparticles in sandwich alternating bilayers endow the modified AEMs with effective antibacterial activities of Escherichia coli. These results are indicative of the desired fouling resistant for ED process. The facile fabrication process and superior performances of modified AEM suggest that the as-prepared “sandwich”-like structure modified AEM is potentially applicable in ED for separation of monovalent and multivalent anions. [ABSTRACT FROM AUTHOR]

The development of stable ion exchange membranes applied in organic solution systems can expand the scope of practical applications. In this work, to explore the organic solvent anion exchange membranes (AEMs), a series of pyridine salt side-chains grafted poly(2,6-dimethyl-1,4-phenyl oxide)-based AEMs have been prepared for electrodialysis (ED). It is interestingly found that the as-prepared AEMs bear 3D network structure. Investigation demonstrates that the optimized AEM (BPPO-APy-6C) has an acceptable surface area resistance of 5.93 Ω·cm2 and the low swelling ratio of 2.5 % in DMSO. As for BPPO-APy-6C AEM exposed to a mixture solvent of 60 % DMSO +40 % water for 90 d, no visible appearance change is observable, indicating the improved organic solvent resistance. This has also been verified by the high desalination ratio (98.0 %) of ED with AEM after being exposed to 20 % DMSO (aq.) for 20 d. In addition, the DMSO-treated BPPO-APy-6C AEM-based ED filled with DMSO-containing 0.5 M NaCl solution shows the similar desalination ratio to that of ED with 0.5 M NaCl solution (aq.), suggesting its superior capacity of tolerating polar organic solvent. It is reasoned that the cross-linked structure and hydrophobicity of alkyl segments within AEM significantly contribute to the enhanced organic solvent resistance. [Display omitted] • A series of pyridine salt-side chains grafted PPO AEMs has been prepared. • The optimized AEM shows the low swelling ratio of 2.5 % in DMSO at room temperature. • The as-prepared AEM exposed to 60 % DMSO (aq.) for 90 d still remains integrity. • The DMSO-treated AEM shows desalination ratio of 98.0 % and organic solvent resistance. [ABSTRACT FROM AUTHOR]

• Two series of side-chain-type polysulfone-based AEMs were prepared via menshutkin reaction. • The optimized AEM exhibits the low area resistance, and good alkaline stability in ED process. • The optimized AEM show the better NaOH enrichment performance than commercial AEM. • The investigation on AEM of this type suggests its potential ED application for alkali enrichment. To meet the need of efficient resource utilization, developing stable and efficient anion exchange membranes (AEMs) for alkaline enrichment application is of significance. In this work, we designed four polysulfone-based side-chain-type AEMs with several cations and different length of spacers per chain, to explore the structure-property relationship and obtained AEMs with high performance for alkaline enrichment via electrodialysis (ED). Our investigation demonstrates that, the optimized AEM (CM-TQ6Q6Q-1, 1.38 mmol·g−1) exhibits low swelling ratio of 8.9%, low area resistance of 2.48 Ω·cm2, acceptable OH– conductivity of 13.7 mS·cm−1. In addition, this AEM also shows relatively good alkaline stability with the IEC retention of 96.7% relative to the original IEC, suggesting the potential application of alkaline enrichment via electrodialysis (ED). After 5-times NaOH enrichment tests in ED, CM-TQ6Q6Q-1 AEM shows an efficient ED performance with alkaline concentration times of ~1.8 (current efficiency: ~90.0%; energy consumption: 8.47 kWh·kg−1), and maintains 96.4% of its original IEC, which are even comparable to those from commercial AEM (Neosepta AHA). The results demonstrate that the as-prepared AEM shows the promising potential ED application for alkali enrichment from the alkaline waste water. [ABSTRACT FROM AUTHOR]

The use of electrodialysis (ED) fabricated with proton blocking anion exchange membranes (AEMs) is a promising method to realize waste acid reclamation. To develop AEMs with low proton leakage, in this work, we designed a series of N -methylpiperidine (MPRD)-functionalized poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) cross-linked by weak base 1,3-di-4-piperidylpropane (DiPRD). Our investigations demonstrate the weak base cross-linker could enhance the density of membrane matrix and reduce the hydrophilicity of AEM matrix, which have been verified by thermogravimetric analysis and water absorption with low swelling ratio of 2.43%. Benefit from the unique structure with denser membrane matrix and additional protonated weak base piperidine structure, the acid blocking performance of the optimized crosslinked AEM was enhanced with the H+ concentration of 1.98 M in concentrate cell during 24 h-ED process at current density of 20 mA cm−2 (initial H+ concentration: 1.0 M), outperforming the AEM without cross-linking structure (1.73 M). Nevertheless, it was found that the small-sized proton diffusion in ion-nanochannels of AEM and the aged membrane matrix in ED process with high sulfuric acid concentration resulted in proton leakage to some degree. As a result, a trade-off between the proton blocking and sulfate ion transport of the cross-linked AEMs is achieved. It is believed that this study can provide a guideline for designing advanced proton blocking AEMs. Image 1 • Three piperidinium-functionalized cross-linked AEMs were fabricated for acid enrichment. • Weak base cross-linker renders the crosslinked AEMs with low swelling ratio of 2.43%. • Acid blocking performance of crosslinked AEM outperforms the one without cross-linking. • The moderate concentration limitation values indicate the proton leakage to some degree. [ABSTRACT FROM AUTHOR]

A facile membrane surface modification process for improving permselectivity and antimicrobial property was proposed. A polydopamine (PDA) coating was firstly fabricated on pristine anion exchange membrane (AEM), followed by in situ reduction of Ag without adding any extra reductant. Finally, 2,5-diaminobenzene sulfonic acid (DSA) was grafted onto PDA layer via Michael addition reaction. The as-prepared AEM exhibited improved permselectivity (from 0.60 to 1.43) and effective inhibition of bacterial growth. In addition, the result of the long-term (90-h continuous electrodialysis) test expressed the excellent durability of the modified layer on membrane surface, because the concentration of Cl− and SO42− in diluted chamber fluctuated ~0.024 and 0.030 mol·L−1 with no distinct decline. The method described in this work makes the full use of multifunctional PDA layer (polymer-like coating, in situ reduction and post-organic reaction), and a rational design of functional AEM was established for better practical application. [ABSTRACT FROM AUTHOR]

In recent years, the electrodialysis (ED) technology has gained substantial attention for its role in recovering sulfuric acid from industrial wastewater. However, the typical anion exchange membranes (AEMs) have been known to exhibit notable proton leakage during ED, which can severely hinder the efficiency of acid concentration. To overcome this issue, we utilized a substrate made of poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP). This choice capitalizes on the presence of fluorine-containing groups for enhanced acid stability and tertiary amine groups to minimize water content, resulting in a significant improvement in proton-blocking capabilities of the AEMs. It is worth noting that, through a combination of partial cross-linking and quaternization, these AEMs not only maintain their acid concentration performance but also substantially reduce energy consumption. Additionally, we conducted a thorough analysis of the delicate balance between current efficiency and energy consumption in acid recovery systems. In contrast to conventional AEMs and commercially available proton-blocking membranes such as ACM, we highlight the exceptional acid concentration capability (C H + = 1.28 M) and the low energy consumption (3.3 kWh/kg) of AEM-1.2. This research breakthrough marks a significant advancement in the development of acid-blocking AEMs and strongly advocates for more efficient sulfuric acid recovery from industrial wastewater. [Display omitted] • A series of acid-blocking AEMs based on PVDF-HFP has been prepared. • The as-prepared AEM was partially quaternized to reduce energy consumption. • The final concentration of AEM prepared is better than that of commercial AEM. • The problem of poor acid enrichment performance of traditional AEMs was solved. [ABSTRACT FROM AUTHOR]

• A series of AEMs based on imidazolium functionalized poly(vinyl chloride) has been prepared. • Micro-structure of PVC AEMs was tuned by the lengths of alkyl side-chains on imidazolium. • Acid blocking performance of as-prepared AEM outperforms the commercial Neosepta ACM. • The maximum concentration of H+ enriched by the optimized AEM is achieved to 1.81 M. Electrodialysis (ED) technology equipped with proton blocking anion exchange membranes (AEMs) has great potential applications in recovering acidic wastewater. To develop high performance proton-blocking AEMs, in this work, a series of imidazolium functionalized poly(vinyl chloride) (PVC) AEMs are designed. In particular, the length of alkyl side chains tethered on the imidazole compound is optimized to adjust the micro-structure of AEM. Our research demonstrates that the density of 1-butylimidazole functionalized PVC AEM matrix is enhanced, which has been proved by water uptake and thermogravimetric analysis. Hence, the acid blocking performance of optimized AEM (PVC-Im-4C) is strengthened. The maximum concentration of H+ in concentrate chamber of electrodialyser enriched by the PVC-Im-4C AEM is 1.81 M through the 24 h ED process at a current density of 20 mA·cm−2 (the initial concentration of hydrogen ions: 1.0 M). The result suggests that the optimized PVC-Im-4C AEM with long alkyl side chain on imidazole shows the excellent capacity in acid enrichment. This work should provide guidance for the follow-up design of the advanced proton blocking AEMs. [ABSTRACT FROM AUTHOR]

Recovery of sulfuric acid from industrial wastewater via electrodialysis (ED) has become a hot topic recently. Since the commercially used anion exchange membranes (AEM) generally lead to the severe proton leakage during ED process, the efficiency of the acid recovery was seriously affected. In this work, a series of proton blockage cross-linking AEM has been prepared by modifying poly(vinylidene fluoride- co -hexafluoropropylene) (PVDF- co -HFP) with 1-vinylimidazole, followed by crosslinking with 1,4-dibromobutane. Our investigation demonstrates that the as-prepared PVDF- co -HFP-based AEM has the observable asymmetric structure on the two sides of the AEM with a smooth and dense surface and a rough and porous surface. The asymmetric structure and the hydrophobicity of the fluorinated backbone of AEM render the improved proton blocking performance, and the increased electrical efficiency and reduced energy consumption of acid recovery. For example, the optimized AEM (AEM-0.5) exhibits the acid concentration with the values of c H + = 2.04 M (initial proton concentration: 1.0 M) in concentrate cell during 12 h-ED process at current density of 20 mA cm−2 and low energy consumption of 1.75 kw·h·kg−1 relative to the commercial NEOSEPTA® AHA and proton blockage ACM AEM. It is believed that this study can provide a guideline for designing advanced proton blocking AEMs. [Display omitted] • A strategy for the preparation of crosslinked AEMs with asymmetric structure was reported. • The as-prepared AEMs show the good acid stability. • The as-prepared AEMs have potential applications in acid concentration. • The optimized AEM shows high acid concentration (2.04 M) and low energy consumption (1.75 kw·h·kg−1). [ABSTRACT FROM AUTHOR]

A kind of modified anion exchange membranes has been prepared by surface modification which enabled imparting antibacterial and anti-bacterial adhesion properties. [Display omitted] • Anion exchange membrane (L-PDA@ABS-Cl) with N-chloramine structure was synthesized by surface modification. • The L-PDA@ABS-Cl shows excellent antibacterial and anti-bacterial adhesion properties. • The difference between pristine AEM and L-PDA@ABS-Cl in desalination is slight. • The hydrophilicity was improved on the basis of little change in electrochemical performance. In this work, a series of modified anion exchange membranes (AEMs) has been prepared via self-polymerization of L-dopa on the surface of commercial AEM (Fuji I type), followed by grafting the 4-amino-benzenesulfonic acid monosodium salt (ABS) on L-polydopamine thin layer. The chemical structures of modified AEMs were confirmed by the FTIR and XPS spectra. Our investigation demonstrates that the surface resistance of the modified AEM (L-PDA@ABS-Cl) increases slightly from 1.90 Ω cm2 to 2.37 Ω cm2 and the hydrophilicity of L-PDA@ABS-Cl significantly improves, verifying by the decreased water contact angles from 86.42° to 67.25°. The difference between pristine AEM and L-PDA@ABS-Cl in desalination rates only remained less than 4% throughout the test of 240 min. The modified AEMs have the negatively charged functional layers which produce an electrostatic repulsion effect and negatively charged bacteria cannot attach to the membrane surface. As a result, L-PDA@ABS-Cl shows good performance on fouling resistance, good inhibition effect on Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). Low surface resistance and superior foul inhibition performance indicate the potential application of modified AEMs in electrodialysis (ED). [ABSTRACT FROM AUTHOR]

• A novel TiO 2 @Ag coating with photocatalysis activity on the AEM has been designed. • TiO 2 @Ag and electrochromic AEM achieve synergistic visible light photocatalysis. • The optimized AEM shows effective photocatalytic degradation and anti-biofouling activity. • Optimized AEM offers potential for sustainable water purification and desalination. Membrane-contamination during electrodialysis (ED) process is still a non-negligible challenge, while irreversible consumption and unsustainability have become the main bottlenecks limiting the improvement of anion exchange membranes (AEMs) anti-contamination activity. Here, we introduce a novel approach to design AEMs by chemically assembling 4-pyndinepropanol with bromomethylated poly(2,6-dimethyl-1,4-phenylene oxide) (BPPO) in an electrochromic-inspired process. Subsequently, the co-mingled TiO 2 @Ag nanosheet with the casting-solution were sprayed onto the surface of the substrate membrane to create a micrometer-thick interfacial layer. The addition of Ag nanoparticles (NPs) enhances the active sites of TiO 2 , resulting in stronger local surface plasmon resonance (LSPR) effects and reducing its energy band gap limitation (From 3.11 to 2.63 eV). Post-electrodialysis electrochromic AEMs incorporating TiO 2 @Ag exhibit synergistic enhancement of sunlight absorption, effectively suppressing photogenerated carrier binding and promoting migration. These resultant-membranes demonstrate significantly improved bacterial inhibition properties (42.0-fold increase for E. coli) and degradation activity (7.59-fold increase for rhodamine B) compared to pure TiO 2 membranes. Importantly, they maintain photocatalytic activity without compromising salt-separation performance or stability, as the spraying process utilizes the same substrate materials. This approach to rational design and regulation of anti-contamination AEMs offers new insights into the collaborative synergy of color-changing and photocatalytic materials. [Display omitted] [ABSTRACT FROM AUTHOR]

Proton blocking anion exchange membrane (AEMs) can be used to treat various of acidic wastewater (i.e., enrich the recovered acid from acidic wastewater). In this work, four AEMs based on aliphatic chain segment imbedding poly(arylene ether sulfone)s bearing salt-terminated side-chains have been prepared for acid enrichment by electrodialysis (ED). In particular, the length of flexible aliphatic chain segments (methylenes of –(CH 2) 3 –), –(CH 2) 6 –, –(CH 2) 9 –, and –(CH 2) 12 –) in aromatic poly(arylene ether sulfone) was tuned to tailor the micro-structure. Our investigation demonstrates that the AEM with aliphatic chain segments of –(CH 2) 12 – shows the strongest surface hydrophobicity (water contact angle: 107°) and has the smallest ion clusters (0.75 nm, relative to the other three AEMs with 0.78 nm, 0.80 nm, and 0.81 nm). In ED process, at the current densities of 10 mA cm−2, the maximum concentration of H+ enriched by the AEM is 2.06 M (initial concentration: 1.0 M). The investigations demonstrate that the optimized AEM with stronger hydrophobicity and smaller ion clusters shows the superior capacity of acid concentration relative to commercial AEM (AMX, Astom Japan). This work should be certain guiding significance for designing advanced proton blocking AEMs. [Display omitted] • Four aliphatic chain segment imbedding PAES AEMs bearing side-chains were prepared. • The length of aliphatic segments in aromatic PAES was tuned to tailor the micro-structure. • Acid blocking performance of as-prepared AEM outperforms the commercial AEM. • The maximum concentration of H+ enriched by the optimized AEM is achived to 2.06 M. [ABSTRACT FROM AUTHOR]

Electrically-driven membrane technology plays a crucial role in water treatment and purification, finding applications in various fields like saline water and wastewater desalination, saline concentration and wastewater recycling. The content of this study is based on dually cross-linking and hot-pressing on a PVDF blend, to fabricate a kind of anion exchange membranes (AEMs) having semi-interpenetrating network and thus improve the defect of the traditional heterogeneous AEMs. The research explores the impact of vinyl imidazole (VIM) and dimethylaminoethyl methacrylate (DMAEMA) monomers, primarily or dually cross-linking, and optimizes the membrane properties through a hot-pressing process. Under these optimized conditions, the resulting membranes exhibit robust mechanical properties and outstanding desalination capabilities, achieving an area resistance of 2.56 Ω cm2 (comparable to standard homogeneous membranes), a desalination rate of 97.26% (outperforming the Neosepta AMX: 76.90%), and a salt limiting concentration of 3.1 M (surpassing the heterogeneous AEM and Neosepta AMX). Notably, this synthesis method is characterized by its cheap raw material and low energy consumption. This research offers valuable insights for the advancement and large-scale implementation of anion exchange membrane desalination. [Display omitted] • A series of PVDF-based AEMs having semi-interpenetrating networks has been prepared. • The as-prepared AEMs optimized through a hot-pressing process. • The optimized AEM shows a desalination rate of 97.26% and a salt limiting concentration of 3.1 M. • The electrodialysis performance of optimized AEMs outperforms the commercial membranes. [ABSTRACT FROM AUTHOR]

Proton blocking anion exchange membranes (AEMs), which are employed in electrodialysis technology, show promise in acid recovery from industrial waste. A series of poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) membranes were prepared using (3-aminopropyl)trimethoxysilane (APTMS) and weakly functionalized bases including N-butylimidazole (N-BuIm). Were networked to create AEMs with low leak rates. It was discovered that the appropriate concentration of siloxane crosslinker raised the membrane matrix's density and lowered the AEM matrix's hydrophilicity. Thermogravimetric measurements and water absorption have confirmed this, and the membranes in this series even swell up to 8.61 %. The maximum H+ concentration concentrated by the cross-linked AEM (BPPO/5Si) during the ED with a current density of 10 mA ∙ cm−2 was 2.35 M, which was higher than the concentration concentrated by the uncross-linked AEM (BPPO/OSi), which was 1.90 M (beginning concentration: 1.00 M). The current efficiency was 44.8 % and the energy consumption was only 1.81 kW ∙h∙kg−1. A balance between proton blocking and SO 4 2− ions transport was achieved by the optimized AEM, which exhibited increased hydrophobicity and smaller ion clusters. The improved AEM was found to have fewer ionic clusters and greater hydrophobicity. For cross-linked AEMs, a trade-off between SO 4 2− ions transport and proton blocking was thus accomplished. This work is thought to offer direction for developing sophisticated proton blocking AEMs. [Display omitted] • Imidazole-functionalized siloxane cross-linked AEMs for acid enrichment has been prepared. • (3-Aminopropyl)trimethoxysilane lowers water absorption and enables cross-linking. • The as-prepared AEM exhibits superior acid blocking performance relative to the commercial AEM. • The as-prepared AEM showcases the relatively excellent acid stability in the ED process. [ABSTRACT FROM AUTHOR]

[Display omitted] • A interfacial layer with anti-biofouling property on the AEM has been designed. • The interface layer is strengthened by bio-safety and eco-friendly agents. • The optimized AEM shows effective anti-biofilm and antibacterial activity. • High stability of the as-modified layer in electrodialysis desalination process. Strengthened surface modification via bio-safety and eco-friendly agent requirements, and the development of the antibacterial anion exchange membrane (AEM) has become crucial for resource recovery with water-sustainable management to effectively mitigate bacteria-related fouling control. A synergistic antibacterial system of lysozyme and tetrakis(hydroxymethyl)phosphonium sulfate (THPS) is explored here that is immobilized onto the surface of commercial AEM with L-dopa. Compared to the single biomacromolecule lysozyme, THPS performs a vital role in this functional layer by compensating for the insensitivity of the lysozyme to typical Gram-negative bacteria (Such as E. coli). This system demonstrated excellent antibacterial performance (E. coli and S. aureus were selected as test strains) according to the "contact-sterilization", and the change with contact time was systematically investigated. Based on confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) examination of live and dead bacteria, it was showed that the as-modified membranes by synergistic antibacterial mechanism revealed effective inhibition of biofilm growth. Moreover, these modified layers demonstrated high stability in electrodialysis (ED) desalination systems. The bio-friendly and robust anti-biofouling characteristics of this approach offer valuable insights for constructing antibacterial surfaces in similar applications. [ABSTRACT FROM AUTHOR]

Biofouling is one of significant obstacles decaying the high separation performance and long-term stability of polymer membranes during the application. To explore the desirable anti-biofouling anion exchange membrane (AEM), in this work, a series of modified AEMs having surface antibacterial functional layers on surface has been prepared by using gentamicin and N-chloramine for electrodialysis (ED). The antibacterial functional layer on surface was constructed via chemical assembly. By using CuSO 4 and H 2 O 2 as the trigger, l -dopa was oxidized on surface of commercial AEM (Fuji type II) to form a carboxyl layer. Thereafter, gentamicin was chemically assembled via the amide condensation reaction. It was chlorinated with diluted NaClO solution to endow it with synergistic antibacterial activity by using gentamicin. Investigation demonstrates that the optimized membrane of P(l -Dopa)@GM-Cl has high antibacterial activity against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). Among them, flow cytometry shows that the antibacterial rate of P(l -Dopa)@GM-Cl against E. coli is more than 99%, which is much higher than original membrane (28.4%). P(l -Dopa)@GM-Cl exhibits the enhanced performance in inhibiting biofilm observed by scanning electron microscopy analysis. This work may provide a reference for the construction of anti-biofouling ion exchange membrane. [Display omitted] • An AEM with synergistic antibacterial performance was prepared via chemical assembly. • The optimized AEM shows a good resistance to chemical contamination. • The as-prepared AEM has high antibacterial rate of 99% against both E. coli and S. aureus. • Chemically assembled AEM has inhibition effect of biofilm formation. [ABSTRACT FROM AUTHOR]