Journal of Membrane Science最新文献

{"title":"Structurally engineered graphene oxide (GO) based membranes with “bidirectional-transport” channels for high salinity wastewater desalination via pervaporation","authors":"Lei Jiang ,&nbsp;Tingting Luo ,&nbsp;Bouchra Belaissaoui ,&nbsp;Andres Piña Martinez ,&nbsp;Shushan Yuan ,&nbsp;Daliang Xu ,&nbsp;Tianze Hu ,&nbsp;Yue Wang ,&nbsp;Xin Xiao ,&nbsp;Riri Liu ,&nbsp;Alexander Volodine ,&nbsp;Bart Van der Bruggen ,&nbsp;Pengrui Jin","doi":"10.1016/j.memsci.2026.125206","DOIUrl":"10.1016/j.memsci.2026.125206","url":null,"abstract":"<div><div>High-salinity wastewater (salinity &gt;1.0 wt%) originating from fine chemicals and waste secondary battery recycling presents a significant treatment demand, and efficient membrane concentration technology is considered one of the most promising approaches to address issue. However, traditional two-dimensional (2D) layered membranes, limited by dense interlayer lateral channels, struggle to simultaneously achieve high flux and high selectivity under high-salinity conditions, and the restricted vertical transport path further severely hinders overall flux. Here, we construct a membrane structure that integrates both lateral and vertical transport paths, providing a general strategy to overcome the inherent trade-off between flux and selectivity in membrane separation. We proposed ethylenediamine (EDA) bridged nanoporous graphene oxide (GO) membrane (E-NP) constructs a mass transfer channel with \"bidirectional transport\" characteristics. Specifically, to accelerate vertical mass transfer, GO nanosheets were first etched to introduce nanopores of approximately 10 nm in sheets, while simultaneously reducing their lateral size by about 45 %. Subsequently, EDA was covalently grafted onto adjacent porous nanosheets, expanding the lateral transport channels and introducing hydrophilic amide sites, while also facilitating the adsorption and diffusion of water molecules. The ultrathin E-NP membrane prepared by vacuum-assisted filtration had a thickness of approximately 100 nm and achieved high water fluxes of 39.7 and 89.5 kg m⁻² h⁻¹ at 40 °C and 70 °C, respectively, while maintaining a desalination rate of approximately 99.80 % even with a feed salinity as high as 14.0 wt%. This is owning to the synergistic acceleration effect between the vertically aligned nanopores and the EDA mediated lateral channels rich in water binding sites, the flux of the E-NP membrane was increased by 149.7 % compared to the original GO membrane.</div></div>","PeriodicalId":368,"journal":{"name":"Journal of Membrane Science","volume":"744 ","pages":"Article 125206"},"PeriodicalIF":9.0,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146075895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reinforcing ion-cluster connectivity via hyperbranched phosphonium units for high-performance and durable AEMWE membranes","authors":"Wooseok Lee ,&nbsp;Soomin Jeon ,&nbsp;Youngjin Seo ,&nbsp;Kyungwhan Min ,&nbsp;Hyeonjun Maeng ,&nbsp;Jungmin Kim ,&nbsp;Chihoon Park ,&nbsp;Tae-Hyun Kim","doi":"10.1016/j.memsci.2026.125203","DOIUrl":"10.1016/j.memsci.2026.125203","url":null,"abstract":"<div><div>Anion exchange membrane water electrolysis (AEMWE) technology has been actively researched for the production of green hydrogen as a next-generation clean energy source, with a primary focus on developing high-performance anion-exchange membranes (AEMs). However, the relatively low ionic conductivity and alkaline stability of AEMs can compromise both the performance and durability of AEMWE systems. Recent studies have reported the introduction of branched structures to enhance microphase separation, thereby improving the ionic conductivity and stability of AEMs. In this study, hyperbranched triphenylphosphine units were incorporated into linear poly (<em>para-</em>terphenyl piperidinium) (QPpTP), and the central phosphorus atom was functionalized into phosphonium (P⁺), yielding branched polymers with an ion-conducting group as the branched unit (b-QP<em>m</em>-QPpTP, <em>m</em> = 5, 7.5, 10). Triphenylphosphonium introduction enabled strong P⁺-OH^- interactions, simultaneously achieving high water uptake, low swelling ratio, and excellent dimensional stability. Notably, b-QP5-QPpTP exhibited enhanced ion-cluster connectivity and a high OH⁻ conductivity of 155.76 mS cm⁻¹ at 80 °C. It also demonstrated outstanding water electrolysis performance of 6.98 A cm⁻² at 2.0 V, as well as excellent long-term durability with a negligible voltage increase of 0.54 mV h⁻¹ over 250 h, confirming its potential as a high-performance branched AEM material for next-generation AEMWE applications.</div></div>","PeriodicalId":368,"journal":{"name":"Journal of Membrane Science","volume":"744 ","pages":"Article 125203"},"PeriodicalIF":9.0,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146076315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimization of ion-regulated polybenzimidazole membrane structure for iron–chromium redox flow battery application","authors":"Meiqi Fei,&nbsp;Huan Zhang,&nbsp;Shuqi Liu,&nbsp;Ziang Chen,&nbsp;Haochang Li","doi":"10.1016/j.memsci.2026.125258","DOIUrl":"10.1016/j.memsci.2026.125258","url":null,"abstract":"<div><div>Polybenzimidazole (PBI) membranes exhibit high structural stability and robust ion-blocking capabilities owing to their dense network structure. However, this compactness hinders proton transport, restricting the application of PBI membranes in iron-chromium redox flow batteries (ICRFBs). Herein, we adopt a dual-regulation strategy employing hydrogen ions (H⁺) and salt ions (Na⁺, K⁺, Ca²⁺) to modulate the PBI matrix. This approach enables non-fluorinated membranes to achieve current densities of 200 mA cm⁻² while maintaining stable performance at 50 °C. Protonation of PBI via 2 M phosphoric acid introduces positive charges, generating interchain electrostatic repulsion. This process increases expands the polymer network. Notably, Na⁺ exhibits stronger π-interactions with the benzimidazole (BI) rings compared to K⁺ and Ca²⁺. These interactions promote chain alignment and enhance electrostatic associations with charge-balancing ions (Cl⁻) within the mPBI-Na membrane. The synergistic regulation by H⁺ and Na⁺ optimizes the membrane network structure, thereby facilitating proton conduction. Consequently, the mPBI-Na membrane demonstrates a low area-specific resistance of 51.7 mΩ cm² and retains 70% energy efficiency over 400 cycles at 200 mA cm⁻² in ICRFBs. This study establishes a facile ion-tuning methodology, providing a viable route for optimizing PBI membrane network structure in advanced energy storage applications.</div></div>","PeriodicalId":368,"journal":{"name":"Journal of Membrane Science","volume":"745 ","pages":"Article 125258"},"PeriodicalIF":9.0,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146172330","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-level application of microscale pumping forces: study on pre-enrichment of trace heavy metal ions using dual membrane chips","authors":"Zhao Cui ,&nbsp;Yajing Zhang ,&nbsp;Hao Shen ,&nbsp;Fei Gao ,&nbsp;Hui Jia ,&nbsp;Wang Jie","doi":"10.1016/j.memsci.2026.125243","DOIUrl":"10.1016/j.memsci.2026.125243","url":null,"abstract":"<div><div>This study explores the multi-level application of microscale pumping forces in both forward osmosis (FO) and electroosmotic (EO) processes, using low-concentration Co²⁺ ions as the enrichment target. The results of numerical calculations combined with experimental verification indicate that the pumping forces actively promotes the transport of ions through the membrane in the electroosmotic unit. The pumping action enhances transport by directly driving ions across the membrane and increasing their contact frequency with the surface, thereby improving capture efficiency under an applied electric field. The enhancement is dual in nature: the pumping effect directly propels ions across the membrane while simultaneously increasing their contact with the membrane surface, which collectively maximizes capture efficiency. The concentration evaluation results of FO-EO integrated chip under pump effect indicate that smaller channels and more parallel channels will generate stronger electric field gradients and more obvious interface interactions, thereby promoting ion migration. Meanwhile, channel geometry and wall morphology have been shown to affect the concentration performance of the system by changing the dynamic contact angle. Among them, the axial folding modification of the channel wall significantly shortened the enrichment time, reducing the enrichment time by three times at 105V. Leveraging this enhancement, the chip reduced the AAS detection threshold for Co²⁺ by two orders of magnitude, from 1.21 × 10⁻⁶ mol/L to 1.21 × 10⁻⁸ mol/L, in just 30 min. This performance underscores the promise of the electroosmotic pump effect for enabling rapid pre-concentration and highly sensitive trace metal detection in integrated FO-EO systems.</div></div>","PeriodicalId":368,"journal":{"name":"Journal of Membrane Science","volume":"745 ","pages":"Article 125243"},"PeriodicalIF":9.0,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146172335","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Forward osmosis-induced hydrovoltaic electricity generation using polyaniline-modified carbon mesh electrodes","authors":"Biao Wei ,&nbsp;Daoqing Liu ,&nbsp;Qi Wu,&nbsp;Qianwei Li,&nbsp;Chunmao Chen","doi":"10.1016/j.memsci.2026.125270","DOIUrl":"10.1016/j.memsci.2026.125270","url":null,"abstract":"<div><div>Forward osmosis (FO) offers a low-pressure route for desalination and water reuse, yet its osmotic driving force is rarely exploited for direct energy recovery. Since hydrovoltaic power generation and membrane separation both involve flow through porous media, integrating them enables simultaneous water purification and electricity harvesting. Here, we develop a forward osmosis-induced electricity generator (FEG) that couples FO water transport with cross-membrane hydrovoltaic power generation. In the FEG, polyaniline-modified carbon mesh electrodes (PANI/C8) are tightly attached to both sides of a semipermeable membrane. The salinity gradient drives water permeation through the membrane and porous meshes, where ion dissociation and migration establish an asymmetric charge distribution across the membrane–electrode assembly. The optimized FEG achieves a water flux of 7.8 L m⁻² h⁻¹, a stable open-circuit voltage of 160 mV, and a short-circuit current that increases from 0.7 to 33 μA upon PANI protonation, evidencing effective coupling between ionic transport in the pores and electronic conduction in the polymer network. A systematic evaluation of water flux, solute rejection, and electrical response under different salinity gradients confirms the simultaneous operation of FO desalination and continuous direct-current output in a pressure-free configuration. This membrane–electrode architecture provides a feasible route to integrate desalination and energy recovery within a single FO module.</div></div>","PeriodicalId":368,"journal":{"name":"Journal of Membrane Science","volume":"745 ","pages":"Article 125270"},"PeriodicalIF":9.0,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146172386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stabilizing MXene membranes via metal ion cage strategy for high-performance ion sieving","authors":"Wenjuan Zhang ,&nbsp;Qiaohong Zhang ,&nbsp;Yuheng Li ,&nbsp;Chunli Liu ,&nbsp;Youliang Wang ,&nbsp;Panpan Zhang ,&nbsp;Hanhong Xu","doi":"10.1016/j.memsci.2026.125267","DOIUrl":"10.1016/j.memsci.2026.125267","url":null,"abstract":"<div><div>The separation of salts and heavy metal ions from wastewater is crucial for environmental protection and resource recovery. Lamellar membranes assembled from 2D nanoflakes have emerged as promising candidates due to their high selectivity and permeability. Here, we reported the fabrication of Metal Ion Cage MXene membranes with enhanced anti-swelling properties using a dual-modification strategy involving K⁺ intercalation and polyethyleneimine (PEI) functionalization. The resulting membranes exhibited excellent structural stability in aqueous solutions, along with outstanding separation performance. The membranes achieved a maximum CR rejection rate of 98.7%, with divalent ions such as Ca²⁺, Cu²⁺, and Pb²⁺ being rejected at rates exceeding 80%, alongside a water flux of ∼38.22 L m⁻² h⁻¹. Mechanistic analysis revealed that K⁺ intercalation enhanced interlayer interactions and limited swelling, while PEI modification strengthened electrostatic repulsion and stabilized the membrane structure. This synergistic strategy provided new insights into the structural design of stable 2D membranes and broadens their applicability in sustainable water treatment technologies.</div></div>","PeriodicalId":368,"journal":{"name":"Journal of Membrane Science","volume":"745 ","pages":"Article 125267"},"PeriodicalIF":9.0,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146172387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydrogen-bonding-driven microstructure reconstruction in polymers of intrinsic microporosity (PIMs) blends for efficient propylene/propane separation","authors":"Bingquan Hua ,&nbsp;Tianyou Lu ,&nbsp;Yingjie Song ,&nbsp;Haojie Ren ,&nbsp;Zhengqi Chen ,&nbsp;Yuhan Li ,&nbsp;Nan Yang ,&nbsp;Zihan Li ,&nbsp;Zongkai Liu ,&nbsp;Guanying Dong ,&nbsp;Jingwei Hou ,&nbsp;Yatao Zhang","doi":"10.1016/j.memsci.2026.125216","DOIUrl":"10.1016/j.memsci.2026.125216","url":null,"abstract":"<div><div>While amidoxime-functionalized PIM-1 (AOPIM-1) membrane shows promise as a candidate for C₃H₆/C₃H₈ separation, its separation performance needs further improvement to meet current sustainable development goals. Here, we implement a polymer blending strategy to enable in situ microstructure reconstruction of the AOPIM-1 membrane for rapid C₃H₆ transport. This approach specifically involves utilizing a blend comprising both partially and fully amidoximed PIM-1 polymers, synthesized by precisely controlling the conversion degree of nitrile groups in PIM-1. Analytical methods and simulations reveal that the enhanced hydrogen bonding interactions within blends underpin the microstructure reconstruction, leading to notable improvements in pore size distribution, fractional free volume, and mechanical/thermal stability. Besides, the coexistence of nitrile and amidoxime groups in blends synergistically enhances C₃H₆ solubility via electrostatic potential matching. The resulting optimized membrane possesses a boosted C₃H₆ permeability of 171.9 Barrer—an increase of 224% over its fully amidoximed PIM-1 counterpart—and maintains a comparable C₃H₆/C₃H₈ selectivity of 27.2, far exceeding the upper bound limit. Our work offers an avenue for developing high-performance PIMs-based polymeric membranes for gas separation applications.</div></div>","PeriodicalId":368,"journal":{"name":"Journal of Membrane Science","volume":"745 ","pages":"Article 125216"},"PeriodicalIF":9.0,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146172338","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Self-crosslinked polybenzoxazine anion exchange membranes derived from long-chain alkylamine bis-benzoxazine for efficient electrodialysis desalination","authors":"Haiyang Shao ,&nbsp;Lei Yuan ,&nbsp;Hao Xu ,&nbsp;Yafei Cheng ,&nbsp;Jiajie Zheng ,&nbsp;Zhijin Su ,&nbsp;Xiaocheng Lin ,&nbsp;Minghong Wu","doi":"10.1016/j.memsci.2026.125271","DOIUrl":"10.1016/j.memsci.2026.125271","url":null,"abstract":"<div><div>The development of anion exchange membranes (AEMs) integrating well-balanced permselectivity (<span><math><mrow><msub><mi>t</mi><mi>i</mi></msub></mrow></math></span>) with minimal area resistance (<span><math><mrow><msub><mi>R</mi><mi>m</mi></msub></mrow></math></span>) is critical for efficient electrodialysis (ED) desalination. Herein, a novel long-chain alkylamine-derived bis-benzoxazine monomer (Bz-LCA) was synthesized via Mannich condensation using N,N-bis(3-aminopropyl)methylamine, m-cresol, and paraformaldehyde. The monomer was subsequently thermally ring-opening polymerized to form a cross-linked base membrane. Quaternary ammonium groups were then introduced through N-alkylation with bromoethane (EtBr), yielding a series of self-crosslinked polybenzoxazine-based AEMs (denoted as QP(Bz-LCA)-Xh, where Xh represents the alkylation duration). Systematic characterization revealed that the alkylation time effectively modulates the membranes' physicochemical and electrochemical properties. Among the prepared membranes, the QP(Bz-LCA)-24h membrane exhibited an optimal balance between <span><math><mrow><msub><mi>R</mi><mi>m</mi></msub></mrow></math></span> (0.89 Ω cm²) and <span><math><mrow><msub><mi>t</mi><mi>i</mi></msub></mrow></math></span> (0.91)). As a result, it delivered superior ED performance, including: a salt removal rate (<span><math><mrow><msub><mi>R</mi><mrow><mi>s</mi><mi>a</mi><mi>l</mi><mi>t</mi></mrow></msub></mrow></math></span>) of 86.4%, an energy consumption (<em>EC</em>) of 5.90 kWh kg⁻¹, and current efficiency (<em>η</em>) up to 93.5%. These metrics comprehensively surpass those of the commercial AMV membrane (<span><math><mrow><msub><mi>R</mi><mrow><mi>s</mi><mi>a</mi><mi>l</mi><mi>t</mi></mrow></msub></mrow></math></span> = 79.4%, <em>EC</em> = 7.37 kWh kg⁻¹, <em>η</em> = 85.7%). Overall, this work proposes a novel and promising molecular design strategy for fabricating cost-effective and high-performance AEMs with demonstrated stability under practical ED operating conditions.</div></div>","PeriodicalId":368,"journal":{"name":"Journal of Membrane Science","volume":"745 ","pages":"Article 125271"},"PeriodicalIF":9.0,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146172461","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Positive microporous polymer nanofiber interlayer tailored polyamide nanofiltration membranes for Li+/Mg2+ separation","authors":"Jia-Chen Zhang ,&nbsp;Bing-Xin Gu ,&nbsp;Hui-Qian Huo ,&nbsp;Yue Shen ,&nbsp;Ming-Jie Yin ,&nbsp;Quan-Fu An","doi":"10.1016/j.memsci.2026.125173","DOIUrl":"10.1016/j.memsci.2026.125173","url":null,"abstract":"<div><div>Construction of positively charged nanofiltration membranes is essential for extracting lithium ions from salt-lake brine to meet the growing demand of the new energy industry. However, conventional membranes suffer from low water permeability due to the large thickness of the fabricated positive-charged polyamide (PA) layer, which increases transport resistance. To address this challenge, a porous interlayer was introduced to regulate the formation of the PA layer and accelerate water transport. Specifically, water-dispersible conjugated microporous polymer (CMP) fibers were synthesized and blended with positively charged polyethyleneimine (PEI) to form a porous, positively charged interlayer. The PEI in this interlayer further participated in the interfacial polymerization process, tailoring the PA morphology and converting the originally negative surface charge to positive. As a result, a dual positively charged membrane was obtained, featuring an enlarged surface area in the PA top layer and a porous structure in the interlayer. Benefiting from the synergistic effects of the Donnan exclusion and reduced transport resistance, the membrane exhibited outstanding separation performance in purifying lithium from a Mg²⁺/Li⁺ mixed solution (mass ratio 20), achieving a water permeance of 11.3 L m⁻² h⁻¹⋅bar⁻¹ and a separation factor of 43.8. Furthermore, the membrane maintained stable performance during a 10-day continuous operation, demonstrating strong promise for practical applications.</div></div>","PeriodicalId":368,"journal":{"name":"Journal of Membrane Science","volume":"744 ","pages":"Article 125173"},"PeriodicalIF":9.0,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146076255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Construction of TpPa-COF interlayered positive nanofiltration membrane for efficient removal of high-concentration heavy metal ions","authors":"Houyi Peng,&nbsp;Wenqi Zhang,&nbsp;Ji Chen,&nbsp;Qi Zhang,&nbsp;Xiao Xiao,&nbsp;Weixing Li","doi":"10.1016/j.memsci.2026.125209","DOIUrl":"10.1016/j.memsci.2026.125209","url":null,"abstract":"<div><div>Polyamide nanofiltration membranes often exhibit reduced rejection rates and flux decline under high ionic strength conditions. In order to efficiently remove heavy metal ions (HMIs) from water, a TpPa-COF interlayered positive nanofiltration membrane was proposed. TpPa-1 COF was synthesized and then reacted with 1,3,5-Benzenetricarbonyl trichloride (TMC) to narrow the pore size. The narrowed pore size from 18 Å to 5.4 Å was designed for rejection of heavy metal ions (&gt;5.8 Å). Then, the membrane was functionalized with polyethyleneimine (PEI) grafting to impart positive surface charges for enhanced HMIs removal. The developed membrane was systematically characterized and evaluated for its physicochemical properties and performance through attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), cold-field emission scanning electron microscope (SEM), and atomic force microscopy (AFM). The fabricated membrane achieved exceptional rejections of Cr³⁺ (99.04 %), Mn²⁺ (97.03 %), Co²⁺ (97.74 %), Ni²⁺ (98.43 %), Zn²⁺ (98.85 %), and Cd²⁺ (99.07 %) at a feed concentration of 1000 ppm. Notably, the membrane maintained the rejection efficiency of 90 % under a higher feed concentration of 6000 ppm, which is better than the commercial NF3 membrane. After 7 days of continuous operation, the rejection of HMIs exceeded 98.4 %, demonstrating the great stability. When treating actual electroplating wastewater, the membrane showed good performance. The removal rate for major ions (Cr(VI), Co²⁺, Cu²⁺, Mn²⁺, Ni²⁺, Zn²⁺) reached from 97.4 % to 99.99 %. The developed membrane exhibited better performance than commercial membrane, demonstrating the practical potential in treating actual wastewater.</div></div>","PeriodicalId":368,"journal":{"name":"Journal of Membrane Science","volume":"744 ","pages":"Article 125209"},"PeriodicalIF":9.0,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146076321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}