Composite Membranes Research Articles

Interfacial Super-Assembly of Vacancy Engineered Ultrathin-Nanosheets toward Nanochannels for Smart Ion Transport and Salinity Gradient Power Conversion.

Ion-selective nanochannel membranes assembled from two-dimensional (2D) nanosheets hold immense promise for power conversion using salinity gradient. However, they face challenges stemming from insufficient surface charge density, which impairs both permselectivity and durability. Herein, we present a novel vacancy-engineered, oxygen-deficient NiCo layered double hydroxide (NiCoLDH)/cellulose nanofibers-wrapped carbon nanotubes (VOLDH/CNF-CNT) composite membrane. This membrane, featuring abundant angstrom-scale, cation-selective nanochannels, is designed and fabricated through a synergistic combination of vacancy engineering and interfacial super-assembly. The membrane shows interlayer free-spacing of ~3.62 Å, which validates the membrane size exclusion selectivity.This strategy, validated by DFT calculations and experimental data, improves hydrophilicity and surface charge density, leading to the strong interaction with K+ ions to benefit the low ion transport resistance and exceptional charge selectivity. When employed in an artificial river water|seawater salinity gradient power generator, it delivers a high-power density of 5.35 W/m2 with long-term durability (20,000s), which is almost 400% higher than that of the pristine NiCoLDH membrane. Furthermore, it displays both pH- and temperature-sensitive ion transport behavior, offering additional opportunities for optimization. This work establishes a basis for high-performance salinity gradient power conversion and underscores the potential of vacancy engineering and super-assembly in customizing 2D nanomaterials for diverse advanced nanofluidic energy devices.

IMAC application of extracellular polymeric substances doped composite membranes for α-amylase immobilization and kinetic studies

Immobilized metal affinity chromatography (IMAC), extensively utilized technique in affinity chromatography, has proven to be highly effective in purifying α-amylase, a crucial enzyme in industrial applications. Here, Poly (2-hydroxyethyl methacrylate) (PHEMA) based composite membranes were fabricated using the radical copolymerization technique in a petri dish. Extracellular polymeric materials (EPS) as the metal binding agent. The attachment of Cu2+ ions to the membranes occurred through the utilization of EPSs (Cu2+-EPS). The membranes having Cu2+-EPS (Cu2+-EPS-PM) were subjected to various characterization techniques, including scanning electron microscopy (SEM), attenuated total reflectance-fourier transform infrared spectroscopy (ATR-FTIR), swelling tests, and surface area measurements. The investigation also encompassed the examination of various factors, including pH, initial α-amylase concentration, temperature, and ionic strength, that exert an influence on the adsorption of α-amylase from an aqueous medium. The Cu2+-EPS-PMs demonstrated maximum adsorption capacity with a value of 54.2 mg/g polymer (pH 5.0 sodium acetate buffer, temperature: 25°C, initial α-amylase concentration of 2 mg/mL). Additionally, it has been observed that the enzyme is able to be used in adsorption and desorption cycles on Cu2+-EPS-PM many times. The investigation also focused on examining the impact of pH, temperature, storage, and operational stability over the activities of both free and immobilized α-amylase. The outcomes showed that immobilization had positive effects on activity.

In situ growth of covalent organic framework on graphene oxide nanosheet enable proton-selective transport in flow battery membrane

Perfluorosulfonic acid (PFSA) is the most widely used membrane material for all-vanadium redox flow batteries (VRFB). However, severe vanadium ion permeation of PFSA membranes remains to be solved. In this work, a series of PFSA-based composite membranes are prepared by introducing two-dimensional continuous covalent organic framework (COF) to achieve enhanced performance. Two dimensional continuous Schiff base network-type COFs (GO/SNW) are synthesized by using the two-dimensional multi-functionalized surface of graphene oxide (GO) as a reaction site. Compared to the original form of agglomerated particles, two-dimensional continuous structure obtained a larger vanadium resistance area. Comparing to conventional PFSA membranes, the special pores of COF have a size sieving mechanism for selectively proton transfer, leading to simultaneously enhancement of proton conductivity and vanadium barrier property. VRFB assembled with PFSA-GO/SNW-7 showed high Coulombic efficiency (CE: 97.47%–98.18 % VS PFSA: 80.73%–91.92 %) and energy efficiency (EE: 93.04%–85.71 % VS PFSA: 77.53%–81.78 %) at 40–120 mA cm−2. In addition, there is no significant decrease in the efficiency of battery assembled with PFSA-GO/SNW-7 after 800 cycle (than 650 h) tests. This work provides a new direction in the design of fillers for mixed matrix membranes.

Prebiotic membrane structures mimic the morphology of alleged early traces of life on Earth

Elucidating compositions of the first cell membranes requires experiments with molecules and chemical conditions representative of early Earth. The molecules used are described as ‘prebiotically plausible’, i.e., they could have formed through abiotic reactions before the emergence of biology. Similarly, the chemical properties of solutions in which these membranes are formed (e.g., pH, temperature, ionic strength) must represent early Earth environments. Here, using confocal and transmission electron microscopy combined with population morphometry, we show that prebiotically plausible molecules, in solutions representative of Hadean submarine alkaline hydrothermal vents, form microstructures with substantial morphological diversity. The microstructures hold the potential for use as analogues of prebiotic processes in the rock record. Additionally, many of the structures are morphologically similar to purported early microfossils, highlighting limitations of morphological interpretation in these studies. Detailed analyses of abiotic microstructures are essential for understanding the earliest life on Earth, and for interpretation of potential biosignatures from extra-terrestrial bodies.

Sulfonated cobalt phthalocyanine/NH2-MIL-125 heterojunction modified electrospun nanofiber membrane for emulsion separation and PMS-photocatalysis synergistic degradation

Membrane technology for wastewater remediation has generated significant interest, however, the single functionality, dull wettability and easy fouling property of the membrane hinder its practical application. Herein, a self-cleaning and multi-use superwetting nanofiber membrane was prepared by electrospinning and subsequent spraying technique. The sulfonated cobalt phthalocyanine/NH2-MIL-125 (CoPcS/NMIL) heterojunction was uniformly enrobed over polyethylene terephthalate (PET) electrospun membrane derived from waste PET bottles. The unique CoPcS/NMIL heterojunction exhibited a dual driving effect in photocatalytic activity and membrane wettability. Therefore, the fabricated CoPcS/NMIL@PET composite membrane demonstrated its capability to address complex water pollution issues effectively. The composite membrane exhibited notable flux permeation ability (538–3180 L m−2 h−1) and achieved excellent separation efficiency of over 99 % for diverse oil-in-water emulsions under the gravity filtration condition. Notably, the membrane can efficiently deal with stubborn high-viscosity crude oil fouling profiting from the photocatalytic self-cleaning function. A high flux recovery ratio of 93.6 % and a low irreversible fouling resistance ratio of 6.4 % can be obtained after 30 min of visible light irradiation. Impressively, CoPcS/NMIL@PET membrane exhibited enhanced permeation flux, separation efficiency and self-cleaning capacity compared to NMIL@PET membrane. Meanwhile, the CoPcS/NMIL@PET-activated peroxomonosulfate (PMS) system exhibited extremely high degradation performance for RhB under visible light with the degradation efficiency of 98 % within 10 min, suggesting its potential in the rapid purification of water-soluble organic pollutants. In addition, the CoPcS/NMIL@PET membrane has good chemical stability and mechanical properties for potential long-term use. Moreover, the demulsification mechanism in oil-water separation and PMS-photocatalysis synergetic mechanism over the fabricated CoPcS/NMIL@PET membrane were also investigated in detail. The research offers a promising approach for the design and fabrication of novel nanofiber membranes that incorporate photosensitizers and MOFs functional surfaces to address the challenges associated with such wastewater treatment.

A correlative study of the genomic underpinning of virulence traits and drug tolerance of Candida auris.

Candida auris is an opportunistic fungal pathogen with high mortality rates which presents a clear threat to public health. The risk of C. auris infection is high because it can colonize the body, resist antifungal treatment, and evade the immune system. The genetic mechanisms for these traits are not well known. Identifying them could lead to new targets for new treatments. To this end, we present an analysis of the genetics and gene expression patterns of C. auris carbon metabolism, drug resistance, and macrophage interaction. We chose to study two C. auris isolates simultaneously, one drug sensitive (B11220 from Clade II) and one drug resistant (B11221 from Clade III). Comparing the genomes, we confirm the previously reported finding that B11220 was missing a 12.8 kb region on chromosome VI. This region contains a gene cluster encoding proteins related to alternative sugar utilization. We show that B11221, which has the gene cluster, readily assimilates and utilizes D-galactose and L-rhamnose as compared to B11220, which harbors the deletion. B11221 exhibits increased adherence and drug resistance compared to B11220 when grown in these sugars. Transcriptomic analysis of both isolates grown on glucose or galactose showed that the gene cluster was upregulated when grown on D-galactose. These findings reinforce growing evidence of a link between metabolism and drug tolerance. B11221 resists phagocytosis by macrophages and exhibits decreased β-1,3-glucan exposure, a key determinant that allows Candida to evade the host immune system, as compared to B11220. In a transcriptomic analysis of both isolates co-cultured with macrophages, we find upregulation of genes associated with transport and transcription factors in B11221. Our studies show a positive correlation between membrane composition and immune evasion, alternate sugar utilization, and drug tolerance in C. auris.

Influence of PEG-PPG-PEG Block Copolymer Concentration and Coagulation Bath Temperature on the Structure Formation of Polyphenylsulfone Membranes

The effect of amphiphilic block copolymer polyethylene glycol (PEG)-polypropylene glycol (PPG)-PEG concentration in the polyphenylsulfone (PPSU) casting solution and coagulation bath temperature (CBT) on the structure, separation, and antifouling performance of PPSU ultrafiltration membranes was studied for the first time. According to the phase diagram obtained, PPSU/PEG-PPG-PEG/N-methyl-2-pyrrolidone (NMP) systems are characterized by a narrow miscibility gap. It was found that 20 wt.% PPSU solutions in NMP with the addition of 5–15 wt.% of PEG-PPG-PEG block copolymer feature upper critical solution temperature, gel point, and lower critical solution temperature. Membrane composition and structure were studied by Fourier-transform infrared spectroscopy, scanning electron and atomic force microscopies, and water contact angle measurements. The addition of PEG-PPG-PPG to the PPSU casting solution was found to increase the hydrophilicity of the membrane surface (water contact angle decreased from 78° for the reference PPSU membrane down to 50° for 20 wt.%PPSU/15 wt.% PEG-PPG-PEG membrane). It was revealed that the pure water flux increased with the rise of CBT from 18–20 L·m−2·h−1 for the reference PPSU membrane up to 38–140 L·m−2·h−1 for 20 wt.% PPSU/10–15 wt.% PEG-PPG-PEG membranes. However, the opposite trend was observed for 20 wt.% PPSU/5–7 wt.% PEG-PPG-PEG membranes: pure water flux decreased with an increase in CBT. This is due to the differences in the mechanism of phase separation (non-solvent-induced phase separation (NIPS) or a combination of NIPS and temperature-induced phase separation (TIPS)). It was shown that 20 wt.% PPSU/10 wt.% PEG-PPG-PEG membranes were characterized by significantly higher antifouling performance (FRR—81–89%, DRr—26–32%, DRir—10–20%, DT—33–45%) during the ultrafiltration of bovine serum albumin solutions compared to the reference PPSU membrane prepared at different CBTs (FRR—29–38%, DRr—6–14%, DRir—74–89%, DT—88–94%).

Acorus calamus L. rhizome extract and its bioactive fraction exhibits antibacterial effect by modulating membrane permeability and fatty acid composition.

Ethnopharmacological relevanceIndia's ancient texts, the Charak Samhita and Sushruta Samhita, make reference to the traditional medicinal usage of Acorus calamus L. In India and China, it has long been used to cure stomach aches, cuts, diarrhea, and skin conditions. This ability of the rhizome is attributed to its antimicrobial properties. Research studies to date have shown its antimicrobial properties. However, scientific evidence on its mode of action is still lacking. Aim of the studyAcorus calamus L. rhizome extract and its bioactive fraction exhibits antibacterial effect by modulating membrane permeability and fatty acid composition. Material and methodThe secondary metabolites in the rhizome of A. calamus L. were extracted in hexane using Soxhlet apparatus. The ability of the extract to inhibit multidrug resistant bacterial isolates, namely Bacillus cereus, Escherichia coli, Acinetobacter baumannii, and Pseudomonas aeruginosa were evaluated using checkerboard assay. Further, the extract was purified using thin layer chromatography, gravity column chromatography, and combiflash chromatography. Structure elucidation of the active compound was done using GC-MS, FT-IR, and UV–Vis spectral scan. The mode of action of the bioactive fraction was determined. Bacterial membrane damage was analyzed using SEM, membrane permeability was determined using SYBR green I and PI dye, leakage of cytoplasmic contents were analyzed using Bradford assay and Fehling’s reagent. The ability to inhibit efflux pump of A. baumannii was determined using EtBr accumulation assay and β-lactamase inhibition was analyzed using nitrocefin as substrate. Also, the biofilm inhibition of B. cereus was determined using crystal violet dye. Moreover, the effect of the bioactive fraction on the fatty acid profile of the bacterial membrane was determined by GC-FAME analysis using 37 component FAME mix as standard. ResultsAcorus calamus L. rhizome hexane extract (AC-R-H) demonstrated broad-spectrum antibacterial activity against all the isolates tested. AC-R-H extract also significantly reduced the MIC of ampicillin against all tested bacteria, indicating its bacterial resistance modulating properties. The assay guided purification determined Asarone as the major compound present in the bioactive fraction (S-III-BAF). S-III-BAF was found to reduce the MIC of ampicillin against Escherichia coli (100–25 mg/mL), Pseudomonas aeruginosa (15–3.25 mg/mL), Acinetobacter baumannii (12.5–1.56 mg/ml), and Bacillus cereus (10–1.25 mg/mL). Further, it recorded synergistic activity with ampicillin against B. cereus (FICI = 0.365), P. aeruginosa (FICI = 0.456), and A. baumannii (FICI = 0.245). The mode of action of S-III-BAF can be attributed to its ability to disturb the membrane integrity, enhance membrane permeability, reduce biofilm formation, and possibly alter the fatty acid composition of the bacterial cell membranes. ConclusionThe bioactive fraction of AC-R-H extract containing Asarone as the active compound showed antibacterial activity and synergistic interactions with ampicillin against the tested bacterial isolates. Such activity can be attributed to the modulation of fatty acids present in bacterial membranes, which enhances membrane permeability and causes membrane damage.

Metabolomics and transcriptomic profiles reveal membrane lipid metabolism being an important factor of sliced taro browning

Cut-surface browning poses a prominent concern when it comes to the storage and consumption of sliced taro. This study evaluated the browning development of sliced taro during cold storage and investigated the underlying browning mechanisms through metabolomics and transcriptomic analyses. Metabolomics analysis revealed a consistent increase in the abundance of metabolites, specifically linolenic acid and its derivatives, as well as hydroperoxides, during the aggravated browning process, suggesting the degradation of membrane lipids, as linolenic acid is a major structural composition of cell membranes. Transcriptomic analysis showed that differentially expressed genes having upregulated expression during the browning process were enriched in the α-Linolenic acid metabolism pathway. Weighted gene co-expression network analysis identified two highly correlated modules with taro slice browning during storage, and genes showing a positive correlation were also enriched in the α-Linolenic acid metabolism pathway. Taken together, these findings indicate that the degradation of membrane lipids during taro browning and the loss of membrane compartmentalization might be key factors contributing to sliced taro browning. Additionally, the upregulation of LOX genes and increased protein activity, along with elevated levels of MDA during browning development, further validate the correlation between membrane lipid peroxidation and taro browning. Overall, this study contributes to our knowledge of the browning mechanisms in fresh-cut foods, providing valuable insights for future research and potential strategies for mitigating browning in sliced taro under cold storage conditions.

Effect and mechanism of solution flow rate during interfacial polymerization on morphology and performance of hollow fiber membranes

Interfacial polymerization (IP) using m-phenylenediamine and trimesoyl chloride (TMC) is an essential method for producing thin-film composite (TFC) membranes. Nevertheless, IP is highly sensitive to changes in process parameters, especially the TMC solutions flow rate during inside-out TFC hollow fibers (HF) production. Research on the impact of flow conditions (i.e., laminar vs. turbulent flows) of these organic solutions on the final membrane characteristics and corresponding mechanism is still lacking. This research tested different TMC flow rates (0.1–2 mL/min) to produce inside-out TFC HF. With a TMC flow rate increase, (i) the leaf-like structures of the polyamide (PA) layer decreased in size, (ii) the thickness of the PA layer slightly increased, and (iii) the pure water permeability decreased. However, the elemental composition, chemical bonds, and NaCl rejection remained stable. Different fluid regimes are considered to affect the performance of HF membranes by affecting the heat dissipation process during IP reaction. A TMC flow rate in the laminar flow state (i.e., low flow rates) is recommended for synthesizing HFs. The current research provides new insights into the IP reaction mechanism of HF membrane, thus offering valuable guidance to optimize and produce membrane products with better performance.

A Homochiral Porous Organic Cage‐Polymer Membrane for Enantioselective Resolution

AbstractMembrane‐based enantioselective separation is a promising method for chiral resolution due to its low cost and high efficiency. However, scalable fabrication of chiral separation membranes displaying both high enantioselectivity and high flux of enantiomers is still a challenge. Here, we report the preparation of homochiral porous organic cage (CC3‐R)‐based enantioselective thin‐film‐composite membranes using polyamide (PA) as the matrix, where fully organic and solvent‐processable cage crystals have good compatibility with the polymer scaffold. The hierarchical CC3‐R channels consist of chiral selective windows and inner cavities, leading to favorable chiral resolution and permeation of enantiomers; the CC3‐R/PA composite membranes display an enantiomeric excess (ee) of 95.2% for R‐(+)‐limonene over S‐(‐)‐limonene and a high flux of 99.9 mg h−1 m−2. This work sheds light on the use of homochiral porous organic cages for preparing enantioselective membranes and demonstrates a new route for the development of next‐generation chiral separation membranes.This article is protected by copyright. All rights reserved

Evaluating the Durability of Perfluorosulfonic Acid Membranes in Fuel Cells Using Combined Open-Circuit Voltage-Accelerated Stability Testing

This study evaluates the chemical and mechanical durability of membranes used in proton exchange membrane fuel cells, highlighting the essential role of electrochemical tests in understanding the relationship between durability and performance. Our methodology integrates various electrochemical evaluation techniques to assess the degradation of perfluorosulfonic acid (PFSA) membranes. The results highlight the considerable improvement in the chemical and mechanical durability of annealed 3M PFSA-reinforced composite membranes (RCMs) compared with their non-annealed counterparts and other membrane types, indicating their superior resilience under challenging conditions. Moreover, the results of using a combined open-circuit voltage-accelerated stability testing protocol demonstrate that annealed 3M PFSA RCMs exhibit enhanced resilience, reaching 18,000 cycles before failure, considerably outperforming NR 211 (5000 cycles) and other membranes. In addition, membrane deterioration over time can be precisely measured by interpreting electrochemical indicators (electrochemically active surface area, circuit resistance, high-frequency resistance, and proton resistance). This approach provides a clear relationship between electrochemical data and durability, offering a comprehensive understanding of how different membranes withstand operational stresses.

Cellulose nanofiber-connected covalent organic framework nanosheets composite membrane for proton conduction

Covalent organic framework (COF) nanosheets have been considered as promising materials for proton exchange membranes (PEM) due to their orderly, adjustable pores and relatively improved membrane forming properties. Here, we introduced the one-dimensional sulfonated bacterial cellulose nanofibers (SBCNF), originating from coconut and binding TpBd-2SO3H nanosheets to prepare a series of SBCNF/TpBd-2SO3H composite membranes. The composite membranes present a typical layered structure due to the presence of SBCNF. Moreover, extensive hydrogen bond network is formed between the embedded TpBd-2SO3H nanosheets and SBCNF, which is beneficial for improving the proton conductivity and mechanical strength of the membrane. As a result, the composite membrane achieved a proton conductivity of 147.5 mS/cm at 80 °C, 100 %RH and a highest tensile strength of 88.49 MPa.

High-performance proton exchange membrane employing water-insoluble hybrid formed by chemically bonding phosphotungstic acid with polydopamine

Heteropolyacids can retain water in a proton exchange membrane to increase proton conductivity at high temperatures and low humidity; however, their high solubility in water leads to leaching, which limits their further application. Herein, we used phosphotungstic acid (HPW) and polydopamine (PDA) particles to prepare a water-insoluble PDA/HPW hybrid (PDW) via hydrothermal reaction. The amino groups of PDA in PDW chemically bonded to HPW and acted as an anchor for HPW. The proton conductivity of the sulfonated poly(ether ether ketone) (SPEEK) composite membrane containing 15wt% PDW (SPEEK/PDW-15) in liquid water was 0.052 S⸱cm–1 at 25 ℃, which was 63% higher than that of the SPEEK control membrane (0.032 S⸱cm–1). The SPEEK/PDW-15 composite membrane also showed stable proton conductivity during 80 days of testing while immersed in water.

Localized surface plasmon resonance and atomic force microscopy study of model lipid membranes and their interactions with amyloid and melatonin

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by the accumulation of amyloid plaques in the brain. The toxicity of amyloid to neuronal cell surfaces arises from interactions between small intermediate aggregates, namely amyloid oligomers, and the cell membrane. The nature of these interactions changes with age and disease progression. In our previous work, we demonstrated that both membrane composition and nanoscale structure play crucial roles in amyloid toxicity, and that membrane models mimicking healthy neuron were less affected by amyloid than model membranes mimicking AD neuronal membranes. This understanding introduces the possibility of modifying membrane properties with membrane-active molecules, such as melatonin, to protect them from amyloid-induced damage. In this study, we employed atomic force microscopy and localized surface plasmon resonance to investigate the protective effects of melatonin. We utilized synthetic lipid membranes that mimic the neuronal cellular membrane at various stages of AD and explored their interactions with amyloid-β (1–42) in the presence of melatonin. Our findings reveal that the early diseased membrane model is particularly vulnerable to amyloid binding and subsequent damage. However, melatonin exerts its most potent protective effect on this early-stage membrane. These results suggest that melatonin could act at the membrane level to alleviate amyloid toxicity, offering the most protection during the initial stages of AD.

Synergistic interfacial polymerization between hydramine/diamine and trimesoyl chloride: A novel reaction for NF membrane preparation

Polyester-amide (PEA) thin film composite (TFC) NF membranes have rapidly evolved towards a competitive performance, benefiting from their remarkable antifouling capability and superior chlorine resistance. In this report, a new concept of synergistic interfacial polymerization is explored, which promptly triggers the reaction between hydramines and trimesoyl chloride (TMC) in the presence of a trace amount of diamines. This rapid-start mode enables the formation of defect-free PEA films without the requirement of catalysis. A comprehensive characterization of physicochemical properties using high-resolution mass spectrometer (HRMS) reveals that the recombination and formation of a “hydramine-diamine” coupling unit plays a decisive role in activating the synergistic interfacial polymerization reaction with TMC molecules. Taking the pair of serinol and piperazine (PIP) as an example, the PEA-NF membrane fabricated with 0.1 w/v% serinol mixed with 0.04 w/v% PIP as water-soluble monomer and 0.1 w/v% TMC as oil phase monomer was found to have a pure water permeability (PWP) of 18.5 L·m−2·h−1·bar−1 and a MgSO4 rejection of 95.5 %, which surpasses almost all the reported PEA NF membranes. Findings of the current research provide more possibilities for the low-cost and rapid synthesis of high-performance PEA membranes aiming for water purification.

Non-precious high entropy alloys and highly alkali-resistant composite membranes based high performance anion exchange membrane water electrolyzers

Cost-effective highly efficient and stable catalysts and alkali-resistant anion exchange membranes (AEMs) are critical for practical applications of anion exchange membrane water electrolyzers (AEMWEs). Here, bifunctional non-precious FeCoNiCuMo high entropy alloys (HEAs), electrochemically deposited on nickel mesh as an anode (FeCoNiCuMo/NM) and on carbon paper as a cathode (FeCoNiCuMo/CP), together with a NiFe layered double hydroxide (LDH) loaded AEM (AEM/LDH), were developed for high performance AEMWEs. The AEMWE thus fabricated delivered an ultrahigh current density of 1777 mA cm−2 at 2 V and exhibited remarkable stability with a less than 0.1% cell voltage increase after a 100-hour operation at 100 mA cm−2 at 50 °C, largely outperforming those of the precious metal based AEMWE, composed of IrO2/NM as the anode and Pt/C/CP as the cathode, 1231 mA cm−2@2 V and 4.57% increase in cell voltages. Composition of the alkali-resistant, hydrophilic, and water electrolysis active NiFe LDH into the AEM improved not only the electrolyte uptake and operational stability, but also the efficiency of the AEMWE, with a 10% boost in current density achieved at 2 V and a reduction in cell voltage increases from 2.94% to 0.0951%. The present development demonstrates the practicality of AEMWEs toward green hydrogen production.

Research on Development and Characterization of Composite Membranes Based on Hybrid Bacterial Cellulose Combined with Glycerol and Vegetable Residues for the Preservation of Fresh Fruit and Food

Research on Development and Characterization of Composite Membranes Based on Hybrid Bacterial Cellulose Combined with Glycerol and Vegetable Residues for the Preservation of Fresh Fruit and Food

Industrial Scale Manufacturing Sub‐10 nm Reverse Osmotic Desalination Membrane on Metallic Single‐Walled Carbon Nanotubes Network

AbstractDifferent from extensively reported carbon nanotubes‐polyamide (PA) composite membranes, this work reports the scalable, low‐cost manufacturing of metallic single‐walled carbon nanotubes network supported PA reverse osmotic desalination membranes. Metallic single‐walled carbon nanotubes (SWCNTs) separated from high‐pressure carbon monoxide conversion (HiPCO) SWCNTs with a diameter ranging from 0.6 to 1.2 nm are deposited on polyethersulfone (PES) films by replacing surfactants around SWCNTs dispersed in aqueous solution, for supporting uniform and smooth sub‐10 nm PA nanofilm formed through aqueous‐organic bilayer interfacial polymerization. The industrial scale manufactured PA/SWCNTs/PES desalination membranes (508 mm × 915 mm) are rolled into spiral wound elements without damage through cutting, gluing, and rolling. The desalination tests on flat PA/SWCNTs/PES membranes exhibits 30 l m−2 h−1 (LMH) under 17.2 bar with 98.45% salt injection when fed with 2000 ppm NaCl at pH = 9. The normalized permeate flux of PA/SWCNTs/PES spiral wound elements is ≈17 LMH under 13.8 bar with 90% salt injection underfed with 2000 ppm MgSO4 at pH = 9–11 condition. The high‐performance sub‐10 nm smooth PA/SWCNTs/PES desalination membranes are fabricated with materials savings and can promote low operation costs compared to conventional 50–100 nm crumpled PA films on any supporting substrates.

Functionalized-MXene-based imprinted MOFs composite membranes for the selective separation of ribavirin

The evident decrease for membrane-treated performance in response to multi-component mixture greatly limited its application. Here, we prepared blended nanomolecularly imprinted composite fiber membranes (CXPM-MIMs) with in situ growth of imprinted MOFs on carboxyl functionalized MXene. Through the carboxylate-assisted coordination pathway, a chelation site is provided by the carboxylate-modified MXene to coordinate with NH2-UiO-66, creating a tightly linked NH2-UiO-66/carboxylate-functionalized MXene heterostructure. The key role of the modified carboxyl group can be identified so that it can help to create a strong coordination bond between the two materials. Conventional MOFs typically lack selectivity and specificity. Here, we present a molecularly imprinted nanocomposite MOFs membrane material that exhibits selective adsorption and molecular separation capabilities. Imprinted UiO-66 (Ce) based on diamino-terephthalic acid was synthesized with water as the only solvent without adding any regulator or additive. By adding ribavirin molecules to multicomponent MOFs using a molecular imprinting technique and carrying out adsorption tests (isothermal and kinetic) as well as selectivity testing, we were able to demonstrate this adsorption-separation mechanism. The valuable testing outcomes shown that the as-prepared CXPM-MIMs performed excellently in terms of pemselectivity for ribavirin (RBV) (permselectivity factor β = 4.89, 10.14, 9.23) in addition to exhibiting perfect specific adsorption ability (58.3 mg g−1). The strong permselectivity and particular identification capacity of CXPM-MIMs demonstrated their tremendous potential in the treatment of RBV contamination.