Search

In this study, a series of collagen–chitosan–eugenol (CO–CS–Eu) flow‐casting composite films were prepared using collagen from sturgeon skin, chitosan, and eugenol. The physicochemical properties, mechanical properties, microstructure, as well as antioxidant and antimicrobial activities of the composite membranes were investigated by various characterization techniques. The findings revealed that the inclusion of eugenol augmented the thickness of the film, darkened its color, reduced the transparency, and enhanced the ultraviolet light‐blocking capabilities, with the physicochemical properties of the CO–CS–0.25%Eu film being notably favorable. Eugenol generates increasingly intricate matrices that disperse within the system, thereby modifying the optical properties of the material. Furthermore, the tensile strength of the film decreased from 70.97 to 20.32 MPa, indicating that eugenol enhances the fluidity and ductility of the film. Added eugenol also exhibited structural impact by loosening the film cross‐section and decreasing its density. The Fourier transform infrared spectroscopy results revealed the occurrence of several intermolecular interactions among collagen, chitosan, and eugenol. Moreover, the incorporation of eugenol bolstered the antioxidant and antimicrobial capabilities of the composite film. This is primarily attributed to the abundant phenolic/hydroxyl groups present in eugenol, which can react with free radicals by forming phenoxy groups and neutralizing hydroxyl groups. Consequently, inclusion of eugenol substantially enhances the freshness retention performance of the composite film. Practical Application: ● The CO–CS–Eu film utilizes collagen from sturgeon skin, improving the use of sturgeon resources.● Different concentrations of eugenol altered its synergistic effect with chitosan.● The CO–CS–Eu film is composed of natural products with safe and edible properties. [ABSTRACT FROM AUTHOR]

In this work, novel silicon oxycarbide (SiOC) ceramic composite nanofiltration membranes with high performance were successfully synthesized at low sintering temperatures by gradual dip-coating approach for the first time. The slow dip-coating process facilitated improved wetting and even spreading of the precursor solution across the substrate. This controlled method ensured the formation of uniform and continuous SiOC ceramic membranes without the introduction of substantial defects or irregularities. Consequently, the systematic approach minimized the occurrence of pinholes, cracks and other structural imperfections in the SiOC ceramic membranes. The synthesis of the SiOC separation layer involved the sintering of polymeric polysilicon as precursor, which caused a lower decomposition temperature in contrast to the conventional method employing silicon carbide powder for sintering. The specific feature enabled a sharp decrease in the sintering temperature which was required for the formation of the separation layer. The prepared SiOC ceramic composite nanofiltration membranes exhibited good permeability with high rejection of dye molecules (>95%) and maintained stable water flux for at least 24 h, showing good long-term stability during cross-flow filtration. This progress provides new approach for the fabrication of compact ceramic nanofiltration membranes with low sintering temperatures, high separation efficiency and enhanced stability. [ABSTRACT FROM AUTHOR]

Ceria nanoparticle-based free-radical scavengers for the mitigation of oxidative damage in perfluorosulfonic acid (PFSA)-based polymer electrolyte membrane fuel cells (PEMFCs) suffer from the drawbacks of lowered protonic conductivity and leaching in the acidic environment of a PEMFC. As an alternative to ceria, here we demonstrate that oxidative damage can be mitigated by functionalization of Nafion with 2-Mercaptoethanesulfonic acid (MESA) in different (0.1–1.0 wt%) ratio. The spectroscopic investigation indicated successful functionalization of MESA over the Nafion chain and resulting Nafion-MESA composite membranes displayed improved hydration and swelling behavior, and thermal and mechanical properties. At ≤60 °C (95% relative humidity), the protonic conductivity of composite membranes was higher than/equivalent to that of pristine Nafion membrane; however, at ≥70 °C it was ∼6%–8% lower. At 80 °C, conductivity of Nafion-MESA-0.1 wt%, Nafion-MESA-0.25 wt%, pristine Nafion, and state-of-the-art Nafion-CeO2−1wt% membranes were 1.72 × 10−1, 1.67 × 10−1, 1.8 × 10−1, and 1.6 × 10−1 S∙cm−1, respectively. The fluoride emission rate value for the same membranes were 0.30, 0.17, 1.39, and 0.27 mg∙g−1, respectively, thus indicating that Nafion-MESA membranes can substitute the ceria-based membranes as a chemically stable membrane electrolyte in PEMFCs. [ABSTRACT FROM AUTHOR]

High‐efficiency and sustainable membrane purification technology is highly desirable but unattainable in the field of water treatment. 2D materials are emerging as very promising candidates for water treatment applications. However, membranes assembled by pure 2D materials lack reasonable structural and functional design, usually exhibiting relatively low water permeance, purification performance, and fouling resistance. Here, a mixed‐dimensional membrane is designed to solve the above‐mentioned problems by assembling two kinds of in situ grown 0D@2D functional building blocks of SiO2@GO and TiO2@MXene. Specifically, the obtained membrane exhibits high and maintainable water permeance of 2114 L m−2 h−1 bar−1 as well as high rejection rates toward organic dyes thanks to the plentiful firm water channels constructed by 0D@2D structures and the negative charges on both SiO2@GO and TiO2@MXene, respectively. Moreover, the 0D@2D TiO2@MXene serves as photocatalyst, rendering the composite membrane intriguing self‐cleaning function under UV irradiation, which is verified by the high recovery ratios of water permeance (97.5%) and dye interception rate (98.7%). Thus, this work offers a promising approach for the design of highly efficient and sustainable membrane for separation and purification purposes. [ABSTRACT FROM AUTHOR]

Principal Component Analysis (PCA) serves as a valuable tool for analyzing membrane processes, offering insights into complex datasets, identifying crucial factors influencing membrane performance, aiding in design and optimization, and facilitating monitoring and fault diagnosis. In this study, PCA is applied to understand operational features affecting pervaporation desalination performance of PVA-based TFC membranes. PCA-biplot representation reveals that the first two principal components (PCs) accounted for 62.34% of the total variance, with normalized permeation with selective layer thickness (Pnorm), water permeation flux (P), and operational temperature (T) contributing significantly to PC1, while salt rejection dominates PC2. Membrane clustering indicates distinct influences, with membranes grouped based on correlation with operational factors. Excluding outliers increases total variance to 74.15%, showing altered membrane arrangements. Interestingly, the adopted strategy showed a high discrepancy between P and Pnorm, indicating the relevance of comparing between PVA membranes with specific layers and those with none. PCA results showed that Pnorm is more important than P in operational features, highlighting its significance in both research and practical applications. Our findings show that even know P remains a key performance property; Pnorm is critical for developing high-performance, efficient, and economically viable pervaporation desalination membranes. Subsequent PCA for membranes without specific layers (M1 to M6) and with specific layers (M7 to M11) highlights higher total variance and influence of variables, aiding in understanding membranes' behavior and suitability under different conditions. Overall, PCA effectively delineates performance characteristics and potential applications of PVA-based TFC membranes. This study would confirm the applicability of the PCA approach in monitoring the operational efficiency of pervaporation desalination via these membranes. [ABSTRACT FROM AUTHOR]

Separation membranes based on graphene oxide (GO) have attracted much attention due to their good separation properties. But its instability in water and rejection of divalent salt ions is a problem that needs to be solved urgently. In this study, molybdenum disulfide (MoS2) is intercalated into graphene oxide by adding polyethyleneimine (PEI) solution drop by drop for cross-linking, and then GO/MoS2/PEI composite membrane is prepared by vacuum filtration. As MoS2 hydrophobicity increases frictionless water flow channels to improve water flux, PEI cross-linking improves membrane stability and rejection of divalent salt ions. The modified composite membrane has a high rejection of 94.8 % for Mg2+, and water flux is increased by 30 % relative to GO/PEI membrane. In addition, the rejection of the composite membrane to different salt solutions is investigated by MgCl2, MgSO4, NaCl and Na2SO4 solutions, and the results obtained are, in order, R(MgCl2) > R (MgSO4) > R(NaCl) > R(Na2SO4). This modified composite membrane has great potential for salt ion removal. [ABSTRACT FROM AUTHOR]

In recent years, electro-membranes have garnered attention for their potential to address the limitations of conventional membranes, such as low permeability, poor selectivity, and fouling. Notably, electrospun electrochemical membranes have emerged as promising solutions, offering increased surface area and uniform porosity, leading to enhanced permeability and pollutant rejection in water treatment applications. This comprehensive review systematically analyzes the preparation methods of frequently employed electrochemical membranes, focusing on their characterizations, processes, and essential parameters. Surface modification techniques, nanomaterial integration, and material selection are pivotal aspects explored in this review. Various fabrication methods, including dip coating, sintering, sol-gel, and integrated approaches, are examined in detail, emphasizing their roles in enhancing membrane functionality. The integration of nanomaterials into mixed matrix electrochemical membranes presents opportunities to develop highly efficient composite membranes. Furthermore, this review analyzes into the fabrication processes of both polymeric and ceramic electrochemical membranes, highlighting the need for scaling up production processes and testing these membranes in realworld scenarios to validate their performance. Advancements in electro-membrane technology have facilitated the development of composite membranes that are not only affordable and scalable but also possess tunable physicochemical properties, promising significant advancements in water treatment methodologies. [ABSTRACT FROM AUTHOR]

[Display omitted] • Innovative in-situ growth and layer-by-layer assembly technique for reinforced GO/BiOBr 2D membranes. • Membranes feature high water permeance (493.9 LMH/bar) and high molecular rejection efficiency (>99 %). • GO/BiOBr composite membranes exhibit outstanding photocatalytic self-cleaning performance under visible light. • Provides a viable route for fabricating functionalized GO-based nanofiltration membranes, combining high permeability with self-cleaning capabilities. Graphene oxide (GO) membranes have emerged as promising candidates for water purification applications, owing to their unique physicochemical attributes. Nevertheless, the trade-off between permeability and selectivity, coupled with their vulnerability to membrane fouling, poses significant challenges to their widespread industrial deployment. In this study, we introduce an innovative in-situ growth and layer-by-layer assembly technique for fabricating multilayer GO membranes reinforced with bismuth oxybromide (BiOBr) on commonly employed Nylon substrates. This method allows for the creation of two-dimensional lamellar membranes capable of photocatalytic self-cleaning and tunable nanochannel dimensions. The synthesized GO/BiOBr composite membranes exhibit remarkable water permeance rates (approximately 493.9 LMH/bar) and high molecular rejection efficiency (>99 % for Victoria Blue B and Congo Red dyes). Notably, these membranes showcase an enhanced photocatalytic self-cleaning performance upon exposure to visible light. Our work provides a viable route for the fabrication of functionalized GO-based nanofiltration membranes with BiOBr inclusions, offering a synergistic combination of high water permeability, modifiable nanochannels, and effective self-cleaning capabilities through photocatalysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • A zwitterion-modified fiber substrate was used to fill with SPEEK to prepare PEM. • Zwitterionic interface provided fast channels for proton transport. • High proton conductivity and chemical stability were obtained. • Better DMFC performance than that of commercial Nafion 212 membrane was obtained. Proton exchange membranes with high ionic conductivity and good chemical stability are critical for achieving high power density and long lifespan of direct methanol cells (DMFCs). Herein, a zwitterionic molecule was grafted onto the surface of polyvinylidene fluoride (PVDF) nanofibers to obtain functionalized PVDF porous substrate (SBMA-PDA@PVDF). Then, sulfonated poly(ether ether ketone) (SPEEK) was filled into the pores of SBMA-PDA@PVDF, and further ionic cross-linked via H 2 SO 4 to prepare the composite membrane (SBMA-PDA@PVDF/SPEEK). The basic groups on the zwitterionic interface could not only establish ionic cross-linking with SPEEK to increase chemical stability and reduce swelling, but also serve as the adsorption sites for subsequent H 2 SO 4 cross-linking to significantly enhance proton conductivity. Super-high proton conductivity (165.34 mS cm−1, 80 °C) was achieved for the membrane, which was 2.12 times higher than that of the pure SPEEK. Moreover, the SBMA-PDA@PVDF/SPEEK membrane exhibited remarkably improved oxidative stability of 91.6 % mass retention after soaking in Fenton's agent for 12 h, while pure SPEEK completely decomposed. Satisfactorily, the DMFC assembled with SBMA-PDA@PVDF/SPEEK exhibited a peak power density of 99.01 mW cm−2, which was twice as much as that of commercial Nafion 212 (48.88 mW cm−2). After 235 h durability test, only 11 % voltage loss was observed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two kinds of natural and renewable materials are combined to fabricate novel 2D membranes for osmotic energy conversion. • The heterogeneous membranes help to the balance of the trade-off between ion selectivity and ion flux. • A record power density of ∼16.57 W/m2 is achieved with the synergism of space and surface charge. • The ion transport mechanism is theoretically investigated by numerical simulations based on Poisson and Nernst–Planck models. As promising prospects for renewable power harvesting, two-dimensional (2D) nanochannels for osmotic energy capture in a reverse electrodialysis arrangement have garnered significant attention. However, existing 2D nanochannel membranes have shown limited power generation capabilities due to challenges in balancing ion flux and selectivity. Here, we construct montmorillonite (MMT)/TEMPO-mediated oxidation cellulose nanofibers (TOCNFs) nanocomposite membranes for enhanced ion transmembrane transport. The intercalation of TOCNFs not only enlarges the interlayer distance, but also provides abundant space charge inside the nanochannels. Benefiting from the strong ion selectivity and high ion flux, the composite membrane achieves a remarkable power output of ∼16.57 W/m2 in the gradient of artificial seawater and river water, exceeding that of the state-of-the-art heterogeneous membrane-based osmotic energy conversion systems. Both experimental and theoretical findings confirm that the synergism of space and surface charge plays a crucial role in promoting osmotic energy conversion. This research contributes valuable insights into the optimization of 2D membranes for efficient clean energy harvesting purposes. [ABSTRACT FROM AUTHOR]

[Display omitted] Proton exchange membranes (PEMs) applied in fuel cell technology suffer from the trade-off between fast proton conduction and durable operation involving dimensional stability, mechanical strength, and oxidative resistance. To address this issue, a novel branched polybenzimidazole (brPBI) was synthesized, covalently cross-linked with (3-chloropropyl)triethoxysilane (CTS), and doped with a novel proton conductor FeATMP to prepare brPBI-CTS/FeATMP membranes. The branching degree of brPBI was optimized to achieve high molecular weight while the branching structure offered high free volume, abundant end-groups, and self-cross-linking moiety that enhanced proton conduction and dimensional/mechanical/oxidative stability. Covalent cross-linking with CTS enhanced the dimensional, mechanical, and oxidative stability while improving the water-assisted proton conduction owing to the hydrophilic nature of siloxane structure formed. At 180 ℃, the proton conductivity of the brPBI3-CTS/FeATMP composite membrane reached 0.136, 0.073, and 0.041 S cm−1 at 100 % RH, 50 % RH, and 0 % RH, respectively, while its swelling ratio after immersion in water at 90 ℃ for 24 h was 4.69 %. The performance of the membranes demonstrated that construction of hydrophilic structure by covalent cross-linking was a successful strategy to break the trade-off effect for PEMs. [ABSTRACT FROM AUTHOR]

[Display omitted] The difficulty of recycling and the finite photocatalytic performance of primitive nano-photocatalysts restrict their application in wastewater purification. In this study, a multifunctional membrane with efficient synergistic adsorption and degradation performance was constructed. The nano-photocatalyst layered bimetallic oxide (LDO) was combined with the matrix membrane polyarylether nitrile (PEN) by delayed phase transition technology. The introduced 2-Methylimidazole (2-MeIm) provided a virtual electron transfer pathway between PEN and LDO and enhanced the photocatalytic performance. The results suggested that PEN/LDO/2-MeIm has outstanding removal performance to organic dyes methylene blue (MB). After three consecutive cycles, the reacted membrane can be readily recovered from the system. The MB removal rate remained high at 89.38%, suggesting that the functional membrane is eligible for recycling and reuse. Finally, based on liquid chromatography-mass spectrometry (LC-MS) analysis and density functional theory (DFT) calculations, the mechanism and pathway of MB photodegradation by the PEN/LDO/2-MeIm system were proposed. Therefore, constructing PEN/LDO/2-MeIm membranes in this study may offer a novel perspective on creating eco-friendly and functional PEN-based membranes for practical use in wastewater purification. [ABSTRACT FROM AUTHOR]

[Display omitted] Intelligent shape memory polymer can be potentially used in manufacturing implantable devices that enables a benign variation of implant dimensions with the external stimuli, thus effectively lowering insertion forces and evading associated risks. However, in surgical implantation, biomaterials-associated infection has imposed a huge burden to healthcare system that urgently requires an efficacious replacement of antibiotic usages. Preventing the initial attachment and harvesting a biocidal function upon native surfaces may be deemed as a preferable strategy to tackle the issues of bacterial infection. Herein, a functionalized polylactic acid (PLA) composite membrane assembled with graphene (GE, a widely used photothermal agent) was fabricated through a blending process and then polydimethylsiloxane utilized as binders to pack hydrophobic SiO 2 tightly onto polymer surface (denoted as PLA-GE/SiO 2). Such an active platform exhibited a moderate shape-memory performance upon near-infrared (NIR) light stimulation, which was feasible for programmed deformation and shape recovery. Particularly stirring was that PLA-GE/SiO 2 exerted a pronounced bacteria-killing effect under NIR illumination, 99.9 % of E. coli and 99.8 % of S. aureus were effectively eradicated in a lean period of 5 min. Furthermore, the obtained composite membrane manifested excellent antiadhesive properties, resulting in a bacteria-repelling efficacy of up to 99 % for both E. coli and S. aureus species. These findings demonstrated the potential value of PLA-GE/SiO 2 as a shape-restorable platform in "kill&repel" integration strategy, further expanding its applications for clinical anti-infective treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cu2+-chelated SPEEK membrane with high IEC is prepared. • High mechanical and dimensional stability are observed for SPEEK-Cu membrane. • Proton conductivity of SPEEK-based membranes reaches 0.074 S/cm at −25 °C. • Water states of samples at subzero temperatures are quantified via DSC analysis. • SPEEK-Cu membrane possesses a stronger anti-freezing property. Improving the proton conductivity (σ) of proton exchange membranes at low temperatures is very important for expanding their application areas. Here, sulfonated poly ether ether ketone (SPEEK) membranes were prepared with different sulfonation degrees, and its maximum ion exchange capacity is 3.15 mmol/g for 10 h at 60 °C. Highly sulfonated SPEEK membrane exhibits ultra-high water uptake and excellent proton conductivity of 0.074 S/cm at −25 °C due to its abundant −SO 3 H. Nevertheless, its high swelling ratio and low mechanical strength are not conducive to the practical application of the membrane. Luckily, by employing the chelation of Cu2+ with −SO 3 − on the SPEEK chain, Cu2+-coordinated SPEEK membranes were prepared, and they not only retain high −SO 3 H content but also possess robust mechanical properties and good dimensional stability compared to pristine SPEEK membrane. Meanwhile, the σ of the SPEEK-Cu membrane reaches 0.054 S/cm at −25 °C, and its fuel cell maximum power (W max) reaches 0.42 W/cm2 at −10 °C, demonstrating superior low-temperature performance in comparison to other reported materials. Particularly, water states in the prepared membranes are quantified by low-temperature differential scanning calorimetry. Because much more water bound to the plentiful −SO 3 H and Cu2+ inside the membrane endows it with anti-freezing performance, the decay of the σ and the W max for the SPEEK-Cu membrane is retarded at sub-zero temperatures. It is envisioned that composite membranes comprising metal ions such as Cu2+-SPEEK have a high potential for sub-zero fuel cell applications. [ABSTRACT FROM AUTHOR]

Various electrospun fibrous membranes have been addressed for oil/water separation owing to their advantages of high specific surface ratio, lightweight, and high porosity. However, they are commonly obtained by solution electrospinning of non‐green raw materials, which could cause serious environmental issues. To realize effective oil/water separation, the optimal processing parameters for melt electrospun polylactic acid (PLA) were determined through orthogonal experiments. Subsequently, PLA fibrous films with cellulose nanofiber (CNF) or sodium chloride (NaCl) for oil/water separation were produced via melt electrospinning. The effects of incorporating CNF or NaCl on the physiochemical properties of melt electrospun PLA fibrous membranes were investigated. In contrast to the pure PLA membranes, the obtained PLA/CNF and PLA/NaCl composite membranes exhibit a finer average fiber diameter and an increased porosity. Also, the oil absorption characteristics and oil/water separation abilities of these fibrous membranes were experimentally studied. In contrast to the 84.55% oil/water separation efficiency of melt‐electrospun PLA fibrous membranes, PLA/CNF exhibits the highest oil/water separation efficiency at 93.54%, whereas PLA/NaCl achieves a maximum efficiency of 90.29%. These findings show the applicability of the eco‐friendly PLA‐based melt electrospun fibrous membrane in the treatment of oily wastewater. [ABSTRACT FROM AUTHOR]

3D printed mixed matrix membrane (MMM) thin film, as a novel adsorbent, was introduced for the extraction of two steroid hormones from wastewater and tap water samples before their determination by high-performance liquid chromatography. The designed adsorbent was fabricated as thin film utilizing digital light processing (DLP) 3D printing. The thin film was made of acrylate photo resin, graphitic carbon nitride (g-C3N4), and polyvinylpyrrolidone and its application was investigated for thin film microextraction of 17β-estradiol (E2) and estrone (E1). The morphology of the 3D printed film surface and its chemical changes were studied using field emission scanning electron microscopy and attenuated total reflectance-Fourier transform infrared spectroscopy, respectively. The surface wettability of the proposed MMM films was measured by water contact angle analysis and its porosity was studied by N2 adsorption/desorption analysis. To attain optimal microextraction performance, optimization of both thin film composition and microextraction procedure was conducted, followed by a thorough evaluation of figures of merit under the optimized conditions. The limits of detection and quantitation were determined to be 1.5 and 5 µg L−1 for both E2 and E1. The linear dynamic range for both compounds was from 5 to 150 µg L−1. The method's repeatability was investigated on a single film for 6 extractions, as well as on 3 different films and the relative standard deviation values were 4.43 and 4.91 for E2 and 5.36 and 6.03 for E1, respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • 3D hierarchically-microstructure evaporator with enhanced light utilization and water transport is constructed by a simple two-step method. • Surface functionalization synergizes substrate engineering. • APTES grafting enables MXene with large interlayer spacing and high hydrophilicity. • NWF substrate guarantees low cost, durability, and high performance. • A considerable cost-effectiveness of 89.4 gh−1/$ and outstanding long-term stabilities in harsh conditions are achieved. Recently, the solar-driven interfacial evaporation desalination has attracted more and more attentions due to the advantages of low cost, zero energy consumption, and high water purification rate, etc. One of the bottlenecks of this emerging technique lies in a lack of simple and low-cost ways to construct three-dimensional (3D) hierarchical microstructures for photothermal membranes. To this end, a two-step strategy is carried out by combining surface functionalization with substrate engineering. Firstly, a silane coupling agent 3-aminopropyltriethoxysilane (APTES) is grafted onto an ideal photothermal material of Ti 3 C 2 T x MXene, to improve the nanochannel sizes and hydrophilicity, which are attributed to enlarged interspaces of MXene and introduced hydrophilic group e.g., –NH 2 and –OH, respectively. Secondly, a low-cost and robust nonwoven fiber (NWF) substrate, which has a 3D micron-sized mesh structure with interlaced fiber stacks, is employed as the skeleton to load enough APTES-grafted MXene by a simple soaking method. Benefited from above design, the Ti 3 C 2 T x -APTES/NWF composite membrane with a 3D hierarchical structure shows enhanced light scattering and utilization, water transport and vapor escape. A remarkable evaporation rate of 1.457 kg m−2 h−1 and an evaporation efficiency of 91.48 % are attained for a large-area (5 × 5 cm2) evaporator, and the evaporation rate is further increased to 1.672 kg m−2 h−1 for a small-area (2 × 2 cm2) device. The rejection rates of salt ions and heavy metal ions are higher than 99 % and 99.99 %, respectively, and the removal rates of organic dye molecules are nearly to 100 %. Besides, the composite photothermal membrane exhibits great stabilities in harsh conditions such as high salinities, long cycling, large light intensities, strong acid/alkali environments, and mechanical bending. Most importantly, the photothermal membrane shows a considerable cost-effectiveness of 89.4 g h−1/$. Hence, this study might promote the commercialization of solar-driven interfacial evaporation desalination by collaboratively considering surface modification and substrate engineering for MXene. [ABSTRACT FROM AUTHOR]

BACKGROUND AND OBJECTIVES: Nanoparticles are presently employed in a multitude of applications due to their advantageous features, which encompass simplicity, non-toxicity, affordability, lack of pollutants, and environmentally friendly process. Utilization of Sargassum sp extract for producing nano-copper oxide is environmentally friendly. The study demonstrates the synthesis of nano-copper oxide facilitated by the macroalgae Sargassum sp. and its application in functionalizing cellulose acetate membrane to enhance dye adsorption capacity. The objective of the current study is to assess the properties of the green synthesis product of nano-copper oxide by employing Sargassum sp. macroalgae and its functionalized cellulose acetate membrane for the purpose of dye adsorption. METHODS: The preparation of Sargassum sp. extract involved utilizing quantities of 2.5, 5.0, and 10.0 grams, which were subsequently combined with a copper sulphate solution to yield nano-copper oxide. Nano-copper oxide was characterized using ultra violet-visual spectroscopy, scanning electron microscope - energy dispersive spectroscopy, x-ray diffraction, and fourier transform infrared techniques. Nano-copper oxide was introduced to bacterial acetate produced from pineapple peel waste to make a composite membrane and observed the antibacterial activity against E.coli and S.aureus, and dye adsorption to Methylene Blue, Malachite Green, Metanil Yellow, and Congo Red for 60 minutes contact time. FINDINGS: Nano-copper oxide is successfully synthesized using macroalgae Sargassum sp. proved by wavelength of ultra violet-visual spectroscopy results at 300 nanometer and energy dispersive spectroscopy analysis that denotes the presence of copper at 0.93 and 8.04 kilo electron volt. It has been verified that the inclusion of Sargassum sp. has effectively facilitated the production of nano-copper oxide. The findings from X-ray diffraction analysis reveal that the crystallite size of the nano-copper oxide measures approximately 19.5 nanometers. Adding nano-copper oxide as much as 2.0 weight percent into cellulose acetate membrane reduces membrane crystalline index from 88.6 percent to 85.7 percent but gives benefit in increasing the anti-bacterial activity against Escherichia coli and Staphylococcus aureus. The adsorption capacity is enhanced for Methylene Blue and Malachite Green dyes, whereas it is diminished for Metanil Yellow and Congo Red dyes. CONCLUSION: Sargassum sp. was effectively employed as a reducing agent to synthesize nano-copper oxide, with an optimal concentration of 5.0 grams for achieving green synthesis. The copper metal obtained through green synthesis exhibits a spherical morphology and possesses an average crystallite size of approximately 19.5 nanometers. It has a percentage atomic weight of 60.6 percent. Introducing nano-copper oxide by 2.0 weight percent into bacterial cellulose acetate membrane reduces the crystalline index from 88.6 percent to 85.7 percent. The rise in nano-copper oxide content within the cellulose acetate membrane leads to a proportional increase in the membrane's antibacterial properties. Additionally, the adsorption of cationic dye in cellulose acetate composite is enhanced, while the adsorption of anionic dye is diminished. [ABSTRACT FROM AUTHOR]

Decreasing gas penetration has noticeable effects on the durability and performance of Nafion based proton exchange membranes (PEMs). Experimental studies showed that adding imidazolyl groups into Nafion could reduce the hydrogen permeation in the membrane, while causing the substantial increase in power density. Nonetheless, the microscopic mechanism of doping on the reduction of hydrogen permeation is remain unclear. In this work, molecular dynamics simulation was performed to understand the transport behaviors of hydrogen in polyvinylimidazole (PVMZ)/Nafion composite membranes at the molecular level. The simulation results indicate that there are different degrees of effects about the polymer phase and aqueous domain on the diffusion kinetics of hydrogen in Nafion and PVMZ/Nafion at low and high hydration levels. With the increase of water content, the hydrogen molecules will migrate from the polymer phase to the polymer/water interface in Nafion and PVMZ/Nafion membranes. At low water content, the more free volume and the more pores in Nafion membrane are conducive to the diffusion of hydrogen than that in PVMZ/Nafion membrane to a greater extent. For the aqueous domain, the smaller and the rougher surface of water clusters in PVMZ/Nafion membranes have a certain limiting effect on the diffusion of hydrogen molecules than that in Nafion membranes at high water content. Consequently, at low water contents (λ ≤ 9), the self-diffusion coefficient of hydrogen (D H2) increases slowly from 0.55 to 1.01 (× 10−5 cm2/s) in Nafion membrane and from 0.26 to 0.53 (× 10−5 cm2/s) in PVMZ/Nafion membrane. In contrast, at high water contents (λ ≥ 9), the D H2 increases rapidly from 1.01 to 2.35 (× 10−5 cm2/s) in Nafion membranes and from 0.53 to 1.74 (× 10−5 cm2/s) in PVMZ/Nafion membranes. The current work can provide a fundamental understanding for experimentally designing new type Nafion based PEMs for hydrogen fuel cells. [Display omitted] • A similar but lower diffusion of hydrogen occurs in PVMZ/Nafion than Nafion under different water contents. • There are different effects for polymer phase and aqueous domain on the diffusion kinetics of hydrogen in Nafion and PVMZ/Nafion. • The hydrogen in Nafion and PVMZ/Nafion tends to migrate toward the polymer/water interface as increasing water content. [ABSTRACT FROM AUTHOR]

Using carboxylated graphene oxide (CFGO) as inorganic crosslinking agent, a series of poly (2,6-dimethyl-1,4-phenylene oxide) (PPO) based complex anion exchange membranes (AEMs) with pyridine cations as conduction sites were prepared successfully. The carboxyl modification can improve the dispersibility of inorganic filler in the polymer and provide more crosslinking sites. At the same time, the two-dimensional layered structure of CFGO and a large number of hydrophilic groups provide good ion transport channels. As a result, compared with the original membrane, the crosslinked composite membranes showed better conductivity and chemical stability. Among them, the conductivity of AP-PPO-CFGO2 reached 102.41 mS/cm at 80 °C, and retained about 70% of the conductivity after soaking in 2 M NaOH for 800 h. Furthermore, the AP-PPO-CFGO2 displayed a power density of 277.5 mW/cm2 in a H 2 /O 2 single cell test at 80 °C. • Composite crosslinked anion exchange membrane containing carboxylated graphene oxide. • Carboxylated graphene oxide can improve ionic conductivity. • Crosslinked composite membrane has good dimensional stability. • The single cell achieves the peak power density of 277.5 mW/cm2. [ABSTRACT FROM AUTHOR]

The present investigation focuses on the design and construction of microbial fuel cells (MFCs) using cylindrical composite membranes in the vertical position, in order to treat domestic wastewater and generate electricity. The composite membranes were prepared with natural clay and activated carbon modified with chlorosulfonic acid using a physical mixture of 85 % clay and 15% modified carbon, and they received a heat treatment at 1000 °C to improve their mechanical resistance. Also, the physicochemical characterization of the composite membranes and their precursors was carried out to determine their morphology, functionalities, and chemical composition. In addition, ion transport tests across membranes were performed to evaluate their ion exchange properties. The components of the MFCs include a polypropylene vessel as the anode chamber, a graphite filter as the anode collector, a stainless-steel mesh as the cathode collector, and a cylindrical membrane as the ion exchange material. Different configurations were tested based on the cathode-anode size proportion (1:1, 1:2, and 2:1). The MFCs were operated at room temperature using wastewater from a municipal treatment plant with sodium acetate as a substrate. The stability and durability of the MFCs were evaluated by monitoring the voltage and power density over time. The composition of the wastewater was analyzed before and after each operation cycle. In general, composite membranes of clay and bituminous carbon modified with chlorosulfonic acid showed favorable characteristics for MFCs applications, such as better ion transport and conductivity. Cells using these membranes with a 2 cm electrode spacing and a cathode: anode size proportion of 1:2 demonstrated the best performance in terms of electricity generation and wastewater treatment. These MFCs achieved a power density of 24.76 mW/m3 and successfully powered an LED and digital clock as prototypes and reduced the overall Chemical Oxygen Demand (COD) by 77.96 %. [Display omitted] • Composite membranes of clay-carbon in cylindrical configuration were studied in MFC. • Membranes demonstrated enhanced ion transport and conductivity in MFC. • MFC were optimized using 1:2 cathode:anode proportion with 2 cm electrode spacing. • Power density of 24.76 mW/m3 and a 77.96 % reduction in COD was observed in MFC. [ABSTRACT FROM AUTHOR]

In recent years quantum dot (QDs) based resistive switching devices(memristors) have gained a lot of attention. Here we report the resistive switching behavior of nitrogen-doped graphene quantum dots/Polyvinyl alcohol (N-GQDs/PVA) degradable nanocomposite thin film with different weight percentages (wt.%) of N-GQDs. The memristor device was fabricated by a simple spin coating technique. It was found that 1 wt% N-GQDs/PVA device shows a prominent resistive switching phenomenon with good cyclic stability, high on/off ratio of ~102 and retention time of ∼104 s. From a detailed experimental study of band structure, we conclude that memristive behavior originates from the space charge controlled conduction (SCLC) mechanism. Further transient property of built memristive device was studied. Within three minutes of being submerged in distilled water, the fabricated memory device was destroyed. This phenomenon facilitates the usage of fabricated memristor devices to develop memory devices for military and security purposes. [ABSTRACT FROM AUTHOR]

Flexible electronic devices could collect dynamic motion information of human body for various sharing operations and became increasing importance in strategic emerging fields of the digitization and intellectualization. However, developing a strain sensor with a wide effective sensing range and high sensitivity remains challenging. In this work, smart Wearable polyurethane nanofiber-based graphene oxide powder (GO)/silver nanowires (Ag NWs) composite membrane was fabricated and demonstrated as strain sensors to monitor various human movements. Ag NWs (0.2 wt%) With varying content of GO (0.3, 0.4 and 0.5 wt%) in N, N-dimethylformamide to fabricated different doped membrane (DF) followed interlayers spraying by graphene nanosheets. Finally, the composite film with three-dimensional multilayer structure was obtained, and named as sandwich membrane (SF). The experimental results show that the sensing mechanism of the composite structure is different under different stresses. When the strain was small, DF plays a major role, and when the strain was large, SF plays a major role. The microstructure of sandwich membrane (SF) composed of fibrous layers based on doped membrane (DF) and interlayers spraying by graphene nanosheets determines various sensitivities to relative resistance variation at different stages during deformation process. The DF appears much sensitive at small strain and the SF mainly occurs at large deformation. Especially, the SF with 11 layers presents extremely synchronous output resistance signals with input strain, and its effective strain range widens to 53.16% with 774.19 sensitivity, moreover, when its durability and stability exceed 1000 cycles, its fast response lag time reduces to 0.002 s. [ABSTRACT FROM AUTHOR]

The development of membranes with rapid and selective ionic transport is imperative for diverse electrochemical energy conversion and storage systems, including fuel cells and flow batteries. However, the practical application of membranes is significantly hindered by their limited conductivity and stability under strong alkaline conditions. Herein, a unique composite membrane decorated with functional Cu2+ cross‐linked chitosan (Cts‐Cu‐M) is reported and their high hydroxide ion conductivity and stability in alkaline flow batteries are demonstrated. The underlying hydroxide ions transport of the membrane through Cu2+ coordinated nano‐confined channels with abundant hydrogen bonding network via Grotthuss (proton hopping) mechanism is proposed. Consequently, the Cts‐Cu‐M membrane achieves high hydroxide ion conductivity with an area resistance of 0.17 Ω cm2 and enables an alkaline zinc‐based flow battery to operate at 320 mA cm−2, along with an energy efficiency of ≈80%. Furthermore, the membrane enables the battery for 200 cycles of long‐cycle stability at a current density of 200 mA cm−2. This study offers an in‐depth understanding of ion transport for the design and preparation of high‐performance membranes for energy storage devices and beyond. [ABSTRACT FROM AUTHOR]

Metal organic framework (MOF) films have attracted abundant attention due to their unique characters compared with MOF particles. But the high‐temperature reaction and solvent corrosion limit the preparation of MOF films on fragile substrates, hindering further applications. Fabricating macro‐sized continuous free‐standing MOF films and transferring them onto fragile substrates are a promising alternative but still challenging. Here, a universal strategy to prepare transferrable macro‐sized continuous free‐standing MOF films with the assistance of oxide nanomembranes prepared by atomic layer deposition and studied the growth mechanism is developed. The oxide nanomembranes serve not only as reactant, but also as interfacial layer to maintain the integrality of the free‐standing structure as the stacked MOF particles are supported by the oxide nanomembrane. The centimeter‐scale free‐standing MOF films can be transferred onto fragile substrates, and all in one device for glucose sensing is assembled. Due to the strong adsorption toward glucose molecules, the obtained devices exhibit outstanding performance in terms of high sensitivity, low limit of detection, and long durability. This work opens a new window toward the preparation of MOF films and MOF film‐based biosensor chip for advantageous applications in post‐Moore law period. [ABSTRACT FROM AUTHOR]

Nanofibers have been widely used in the construction of proton exchange membranes(PEM), which can be used to modify Nafion membranes and enhance their mechanical properties. With the addition of nanofibers, some of the sulfonic acid active sites in the perfluorosulfonic acid matrix are occupied, and the conductivity decreases. A covalent organic framework (COF) can be used to compensate for this. In this paper, hybrid COFs modified with sulfonic and pyridine groups were selected and synthesized in situ on polyacrylonitrile (PAN) fibers, and the fibers were placed in a perfluorosulfonic acid matrix to form a sandwich shaped composite membrane. The hybrid COF generates a small fiber-like structure to connect the PAN fibers, which improves the connectivity between three-dimensional nanofibers. This structure also plays a role in enhancing longitudinal proton transport ability of the composite membrane, which provides a new idea in the study of PEM. • In situ synthesis of hybridized COFs of sulfonated pyridines on fibers. • COF synthesis connects fibers to each other and increases longitudinal connectivity. • The fibers are added to the perfluorosulfonic acid solution together with COF to form a sandwich structure. • The prepared composite membrane has high conductivity and performance stability. [ABSTRACT FROM AUTHOR]

As the system with the highest solar hydrogen conversion efficiency, the further improvement of photovoltaic-photoelectrocatalysis (PV-PEC) efficiency is dependent on the light transmittance, activity and stability of the photoanode. Here, a highly permeable BiVO 4 thin film was fabricated through controlled magnetron sputtering. The thickness of the thin film was merely 345 nm, while its transmittance in the visible light range reached as high as 70%. Moreover, large-scale production of such films could be achieved. By incorporating NiFeO x oxygen extraction cocatalyst, under AM 1.5G illumination, the photocurrent density at 1.23 V on reversible hydrogen electrode (RHE) increased to 4.2 mA cm−2 and the incident photon-current conversion efficiency reached 70%. A PV-PEC system was designed to efficiently harness sunlight by integrating the photoanode with a solar photovoltaic panel. Upon connection with the solar photovoltaic panel (with an efficiency of only 7%), spontaneous water decomposition could be achieved, resulting in a solar-to-hydrogen conversion efficiency (η STH) of 4.2% for the series system. This study contributes to the realization of cost-effective and highly efficient PV-PEC hydrogen production. The PV-PEC series system with BiVO 4 thin film photoanode prepared by magnetron sputtering method improves the overall utilization rate of sunlight and realizes spontaneous water decomposition. [Display omitted] • BiVO 4 films with large area and high transmittance can be prepared by low rate controlled magnetron sputtering. • The PEC performance of films was improved by optimizing the magnetron sputtering process and supporting catalyst. • Photovoltaic and photoanode in PV-PEC cells can be irradiated in series to improve the utilization rate of sunlight. [ABSTRACT FROM AUTHOR]

Considering that heavy-metal contamination of seawater is getting worse, building a quick, accurate and portable device for detecting trace zinc in seawater in real time would be very beneficial. In this work, a microfluidic system was developed that includes a planar disc electrode, a micro-cavity for detection, an electrochemical workstation, a computer, a container for waste liquid reprocessing, an external pipeline and other components as well as a graphene/cerium oxide/nano-cerium oxide/Nafion composite membrane was used to modify the planar disc electrode (GR/CeO2/Nafion/Au) to investigate the electrochemical behaviour of Zn(II) using cyclic voltammetry, square-wave voltammetry and orthogonal test methods. Under optimal experimental conditions, the peak reaction current of Zn(II) showed a good linear relationship with the concentration of Zn(II) in the range of 1–900 μg/L with a correlation coefficient of 0.998, and the detection limit of the method was 0.87 μg/L. In addition, the microfluidic system had good stability, reproducibility and anti-interference. The system was used for determining zinc ions in real seawater samples, and the results were very similar to those of inductively coupled plasma–emission spectrometry, demonstrating the practicality of the system for the detection of trace zinc. [ABSTRACT FROM AUTHOR]

This study addresses the need for enhanced antimicrobial properties of electrospun membranes, either through surface modifications or the incorporation of antimicrobial agents, which are crucial for improved clinical outcomes. In this context, chitosan—a biopolymer lauded for its biocompatibility and extracellular matrix-mimicking properties—emerges as an excellent candidate for tissue regeneration. However, fabricating chitosan nanofibers via electrospinning often challenges the preservation of their structural integrity. This research innovatively develops a chitosan/polycaprolactone (CH/PCL) composite nanofibrous membrane by employing a layer-by-layer electrospinning technique, enhanced with silver nanoparticles (AgNPs) synthesized through a wet chemical process. The antibacterial efficacy, adhesive properties, and cytotoxicity of electrospun chitosan membranes were evaluated, while also analyzing their hydrophilicity and nanofibrous structure using SEM. The resulting CH/PCL-AgNPs composite membranes retain a porous framework, achieve balanced hydrophilicity, display commendable biocompatibility, and exert broad-spectrum antibacterial activity against both Gram-negative and Gram-positive bacteria, with their efficacy correlating to the AgNP concentration. Furthermore, our data suggest that the antimicrobial efficiency of these membranes is influenced by the timed release of silver ions during the incubation period. Membranes incorporated starting with AgNPs at a concentration of 50 µg/mL effectively suppressed the growth of both microorganisms during the early stages up to 8 h of incubation. These insights underscore the potential of the developed electrospun composite membranes, with their superior antibacterial qualities, to serve as innovative solutions in the field of tissue engineering. [ABSTRACT FROM AUTHOR]

Considering the high demand for air quality, the development of biomass-based air filtration membranes with high air filtration efficiency and good stability is an urgent task. In this work, polyvinyl alcohol (PVA), gelatin (GA), and cellulose nanocrystals (CNC) were mixed and prepared into a membrane through an electrospinning method for air filtration. After a hydrophobic modification, the modified PVA/GA/CNC composite membrane showed excellent filtration efficiency for PM2.5 (97.65%) through the internal three-dimensional structure barrier and the electrostatic capture effect of the CNC with a negative charge, as well as a low-pressure drop (only 50 Pa). In addition, the modified PVA/GA/CNC composite membrane had good mechanical properties (maximum tensile fracture rate of 78.3%) and high stability (air filtration efficiency of above 90% after five wash-filter cycles and a high-temperature treatment at 200 °C). It is worth noting that the whole preparation process is completed without organic solvents, putting forward a new strategy for the construction of green air filtration membranes. [ABSTRACT FROM AUTHOR]

In this study, an improved PVA/PLA fibrous hemostatic membrane was prepared by electrospinning technology combined with air plasma modification. The plasma treatment was used to modify PLA to enhance the interlayer bonding between the PVA and PLA fibrous membranes first, then modify the PVA to improve the hemostatic capacity. The surfaces of the PLA and PVA were oxidized after air plasma treatment, the fibrous diameter was reduced, and roughness was increased. Plasma treatment enhanced the interfacial bond strength of PLA/PVA composite fibrous membrane, and PLA acted as a good mechanical support. Plasma-treated PVA/PLA composite membranes showed an increasing liquid-enrichment capacity of 350% and shortened the coagulation time to 258 s. The hemostatic model of the liver showed that the hemostatic ability of plasma-treated PVA/PLA composite membranes was enhanced by 79% compared to untreated PVA membranes, with a slight improvement over commercially available collagen. The results showed that the plasma-treated PVA/PLA fibers were able to achieve more effective hemostasis, which provides a new strategy for improving the hemostatic performance of hemostatic materials. [ABSTRACT FROM AUTHOR]

Self-powered wearable pressure sensors based on flexible electronics have emerged as a new trend due to the increasing demand for intelligent and portable devices. Improvements in pressure-sensing performance, including in the output voltage, sensitivity and response time, can greatly expand their related applications; however, this remains challenging. Here, we report on a highly sensitive piezoelectric sensor with novel light-boosting pressure-sensing performance, based on a composite membrane of copper phthalocyanine (CuPC) and graphene oxide (GO) (CuPC@GO). Under light illumination, the CuPC@GO piezoelectric sensor demonstrates a remarkable increase in output voltage (381.17 mV, 50 kPa) and sensitivity (116.80 mV/kPa, <5 kPa), which are approximately twice and three times of that the sensor without light illumination, respectively. Furthermore, light exposure significantly improves the response speed of the sensor with a response time of 38.04 µs and recovery time of 58.48 µs, while maintaining excellent mechanical stability even after 2000 cycles. Density functional theory calculations reveal that increased electron transfer from graphene to CuPC can occur when the CuPC is in the excited state, which indicates that the light illumination promotes the electron excitation of CuPC, and thus brings about the high polarization of the sensor. Importantly, these sensors exhibit universal spatial non-contact adjustability, highlighting their versatility and applicability in various settings. [ABSTRACT FROM AUTHOR]

The new class of microfiltration (MF) membranes based on nanofibrous sub-layers was investigated in this study. To this end, polyethylene terephthalate (PET) nanofibrous layers were produced via electrospinning technique based on PET supports as baking material, and subsequently, the solvent vapor treatment was applied for pore size modification of nanofibrous membranes. Capillary flow porometry and scanning electron microscopy were used to evaluate of pore size and morphology of the membranes, respectively. Moreover, filtration performance was evaluated by water flux and microparticle/bacteria retention. The results showed that average pore size of PET electrospun nanofibrous membrane was greatly reduced from 1.2 to 0.4 µm during modification process. Solvent vapor-treated MF membranes show significantly higher flux and acceptable rejection compared to commercial MF membranes. [ABSTRACT FROM AUTHOR]

Carbon-based materials are widely used in electrical heaters, resistors, battery electrodes, and other applications. Membranous electronic components, with light weight, small volume, extraordinary mechanical flexibility, can be used in microelectronic devices and flexible electronic devices. The C/Si 3 N 4 composite film was prepared by circulating 16% sucrose solution on the coating machine for 4 times and heat treating with nitrogen at 850 °C for 60min. The composite film has excellent electrical conductivity, and the resistivity is 15 mΩ cm at normal temperature (20 °C), and the minimum resistivity can be less than 1 mΩ cm at high temperature. In addition, the composite film maintains the inherent flexibility of silicon nitride fiber paper, and the minimum bending radius is as low as 3 mm. Compared with polymer flexible membranes, C/Si 3 N 4 composite membranes show excellent long-term stability at high temperatures, and the preparation process is green, low cost, easy to operate, and suitable for large-scale production. [ABSTRACT FROM AUTHOR]

A large amount of dye effluents with biodegradable and highly toxic nature from the dyeing and finishing processes has discharged into natural water bodies without adequate treatment, which adversely impacted on aquatic life and human health. Herein, polyvinyl alcohol/agarose/maltodextrin composite membrane (PAM)‐reinforced durian skin fiber is fabricated for methylene blue (MB) uptake from aqueous medium. Structural analyses of the as‐prepared composite membrane are conducted using scanning electron microscopy, Fourier‐transform infrared spectroscopy, water contact angle, and nitrogen adsorption/desorption isotherm measurement. The important influence of experimental conditions including exposure time between adsorbates and adsorbents, initial MB concentration, solution temperature, and pH are also explored. Furthermore, thermodynamic behavior, nonlinear isotherms, and kinetics along with possible adsorption mechanism are provided to attain the insight into the adsorption nature. The results show that PAM‐reinforced durian peel waste possesses high MB adsorption capacity (105.54 mg g−1), which was controlled by diffusion and chemisorption mechanism. The thermodynamics of methyl blue removal on the composite membrane suggest that the adsorption is spontaneous, favorable, and endothermic in nature. This contribution is expected to inspire the efficient utilization of agriculture by‐products into eco‐friendly and biodegradable adsorbents to purify the dye‐contaminated water. [ABSTRACT FROM AUTHOR]

Highlights: Plasma-grafting acrylic acid composite membrane for MABR was prepared. Higher O2 transfer rate and better hydrophilicity for modified membranes than pristine. Modified PVDF membrane demonstrated superior nitrogen removal during startup. Activity of denitrifying bacteria was enhanced in the modified PVDF MABR. Microporous membranes such as polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVDF) often exhibit suboptimal hydrophilicity and microbial adhesion, which impede effective nitrogen removal in membrane-aerated biofilm reactors (MABRs), particularly during initial operational phases. To address this issue, the present study introduced acrylic acid (AA) following plasma treatment (P) to enhance membrane performance, thereby engineering a novel composite material optimized for MABR applications. Four MABRs—Reactor with pristine PVDF membrane (R-PVDF), Reactor with composite PVDF membrane (R-PVDF-P-AA), Reactor with pristine PTFE membrane (R-PTFE), and Reactor with composite PTFE membrane (R-PTFE-P-AA)—were evaluated. The modified membranes displayed enhanced roughness and hydrophilicity, which improved biocompatibility and variably increased the oxygen transfer efficiency. Notably, the R-PVDF-P-AA configuration showed a significant enhancement in the removal rates of NH4+-N and total nitrogen (TN), achieving 78.5% and 61.3%, respectively, which was markedly higher than those observed with the original membranes. In contrast, the modified R-PTFE-P-AA exhibited lower removal efficiencies, with NH4+-N and TN reductions of approximately 60.0% and 49.5%. Detailed microbial community analysis revealed that the R-PVDF-P-AA membrane supported robust commensalism between ammonia-oxidizing and denitrifying bacteria, underpinning the improved performance. These findings highlight the critical role of surface chemistry and microbial ecology in optimizing the function of MABRs. [ABSTRACT FROM AUTHOR]

Lithium metal anode holds great promise due to its highest theoretical capacity and lowest redox potential. However, its practical application is hindered by lithium dendrite growth and exhaustive side reactions, which poses concerns to both cell performance and safety. Herein, a relocatable composite membrane is developed to simultaneously inhibit dendrite growth and stabilize solid electrolyte interphase (SEI) film. The compact packing of hollow multishelled structure (HoMS) provides percolated lithium ion channels and uniform ion flux, while the combined elastic polymer endows membrane structural flexibility to dynamically accommodate volume changes, which results in dendrite‐free lithium deposition inside HoMS and underneath the membrane and stable SEI film restricted to the outer surface of HoMS. Consequently, the membrane‐modified lithium metal half cell achieves an impressive Coulombic efficiency of 99.6% for over 600 cycles. Notably, full cell paired with LiFePO4 cathode stably runs for over 700 cycles, with a decay rate of only 0.045% per cycle, while the one paired with LiNi0.8Co0.1Mn0.1O2 cathode demonstrates a high capacity of 164.1 mAh g−1 at 1 C and a good capacity retention. This HoMS‐based composite membrane opens up new opportunities to realize the practical application of lithium metal batteries. [ABSTRACT FROM AUTHOR]

Textiles with outstanding moisture transport characteristics and excellent flammability is of vital importance for human beings. In this work, the poly(arylene sulfide sulfone)–polydopamine/polyphenylene sulfide–polydopamine/poly(arylene sulfide sulfone) (PASS‐PDA/PPS‐PDA/PASS) composite fibric with multigradient porous structures from macro to submicron levels prepared via micrometer and nanometer fibers for water transport and evaporation has been fabricated. The introduction of PDA can effectively improve the hydrophilicity of the composite membrane. Meanwhile, superhydrophobic PASS layer with beaded structure was obtained by electrospray as the inner layer. It is found that PASS‐PDA‐72 fabric exhibited outstanding water diffusion property (spreading diameter = 10.47 cm) and ultrafast the water evaporation (0.20 g h−1). Meanwhile, the beaded‐structure PASS fabrics with high hydrophobicity (water contact angle is 130°C) was selected to absorb water from the surface of human skin and transport it to the other side to evaporate quickly, giving the surface of human skin a comfortable and dry environment. What is more, the PASS‐PDA/PPS‐PDA/PASS composite membrane exhibited excellent thermal stability (Tdmax = 544°C) and flame retardancy, which will have potential for the application in the field of fire protection. [ABSTRACT FROM AUTHOR]

Oil spills and industrial wastewater discharge have inflicted severe damage upon the ecological environment and human health. Therefore, the development of an environmentally friendly and pollution-free membrane material for oil-water separation is imperative. This study presents the development of a novel oil-water separation material (PP-PPy-pHR) that is environmentally benign and capable of switching between wetting properties. The material was synthesised by dopamine modification, treatment with a pH-responsive polymer and the use of a high-efficiency photothermal layer composed of self-assembled polypyrrole (PPy), and it not only separates incompatible oil-water mixtures but also efficiently separates oil-water emulsions under different pH conditions. Due to the good photothermal effect of PPy, the evaporation rate of PP-PPy-pHR composite membrane loaded with PPy was 3.95 times higher than that of pure water for oily wastewater. In addition, the PPy-pHR composite membrane exhibited excellent durability and high stability in extremely acidic and alkaline solutions, showing remarkable potential for oil-water separation applications. [ABSTRACT FROM AUTHOR]

In this study, a series of novel composite membranes were synthesized utilizing polyethersulfone (PES), sulfonated polyethersulfone (SPES) as base polymer and titanium tungstomolybdate (TWM) as an inorganic ion exchange resin. The membranes were fabricated through the solution casting technique. The composite membranes exhibited enhanced thermal and chemical stability, as well as improved oxidative stability. All the composite membranes demonstrated higher hydrophilicity, with the SPES-TWM composite membranes displaying the lowest contact angle of 65°. The composite membranes also displayed favorable water uptake (up to 26% for SPES-TWM) and lower methanol uptake (maximum 12% for SPES-TWM) and better mechanical stability (maximum of 40 MPa for SPES-TWM). The SPES-TWM composite membranes exhibited the maximum ion exchange capacity of 1.32 meq.g−1. The transport number of 0.95 was obtained for SPES-TWM, which is comparable to the Nafion-117 membrane. The proton conductivity of both membranes increased as the temperature increased. The maximum proton conductivity of 6.3 mScm−1 was observed for SPES-TWM at 60 °C. • Composite membranes based on PES and SPES with nano TWM were prepared. • Composite membranes exhibited thermal stability up to 220 °C, mechanical stability of 44 MPa and good oxidative stability. • SPES-TWM membrane exhibited an IEC of 1.32 meqg−1 and proton conductivity of 6.3 mScm−1 at 60 °C. • SPES-TWM membrane exhibited higher diffusivity and permselectivity than PES-TWM membrane. • PES-TWM membrane displayed methanol permeation of 5.28 × 10−7 cm2s−1. [ABSTRACT FROM AUTHOR]

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-2SO 3 H nanosheets to prepare a series of SBCNF/TpBd-2SO 3 H 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-2SO 3 H 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. [Display omitted] • Natural product coconut was treated to obtain SBCNF as binding agent. • TpBd-2SO 3 H nanosheets were bound with SBCNF to prepare composite membranes. • The hydrogen bond network between SBCNF and CONs facilitates proton transfer. • The composite membrane shows a high proton conductivity of 147.5 mS/cm. [ABSTRACT FROM AUTHOR]

Developing proton-exchange membranes (PEMs) for energy applications is necessary for fulfilling the increasing energy demand without environmental effects. In this study, we prepared composite membranes containing mercaptoethanol-assisted sulfonic acid-functionalized polysiloxanes (MASFPs) and perfluorinated sulfonic acid (PFSA). The MASFP-containing composite membrane (i.e., CMASFP-2) exhibited better membrane properties than the composite membrane prepared without mercaptoethanol (CMASFP-1) and the reference Nafion 212 membrane. Wide-angle X-ray diffraction (XRD) studies revealed a broad peak at 2θ = 17.4° and 39°, indicating that the composite membranes are semicrystalline. Scanning electron microscopy (SEM) analysis revealed that the prepared composite membranes had good morphology, whereas energy-dispersive X-ray spectroscopy analysis revealed that it had siloxane and more sulfonic acid than the pristine PFSA membrane. Thermogravimetric and mechanical strength analyses revealed that incorporating sulfonic acid-functionalized siloxanes improved the thermal stability and mechanical strain of the membrane. The prepared CMASFP-2 membrane had a high ionic conductivity of 0.106 mS cm−1 and an ion-exchange capacity of 1.09 meq·g−1. CMASFP-2 also exhibited lower hydrogen gas permeability than the Nafion 212 and PFSA membranes, demonstrating that it can be used for energy applications. [Display omitted] • A new sulfonic acid-functionalized siloxane was used in composite membranes with PFSA. • The addition of mercaptoethanol enhanced the sulfonic acid amount in the siloxanes. • The CMASFP-2 membrane had a better ionic conductivity and ion-exchange capacity than Nafion 212. • The addition of siloxane improves mechanical strain and lowers H 2 gas permeability. [ABSTRACT FROM AUTHOR]

The development of superior thin‐film nanocomposite (TFN) membranes with good separation performance and anti‐fouling capacity is required to address the larger‐scale freshwater need. In this study, a new citric acid‐functionalized FSM‐16 (CA‐FSM‐16) mesoporous was successfully synthesized and characterized. Subsequently, it was introduced on the surface of the sodium hydroxide/cyanuric chloride‐activated PES membrane to fabricate the CA‐FSM‐16 TFN membrane. It was investigated how various CA‐FSM‐16 loadings affected the overall physicochemical characteristics and performance of the membrane. The SEM analysis confirmed the TFN structure of the fabricated membranes. All manufactured membranes displayed improved hydrophilicity and flux. For the pristine membrane, the salt (Na2SO4) rejection was measured 73.20 ± 2.10%, whereas for the TFN‐0.08 membrane, it was measured 91.40 ± 1.80%. The dye rejection experiment in cross‐flow filtration showed that the TFN‐0.08 membrane had the maximum licorice retention among the membranes (99.10 ± 2.00%). In addition, the CA‐FSM‐16 TFN membranes demonstrated superior antifouling performance, especially the optimum membrane (TFN‐0.08), which showed a high flux recovery ratio (FRR) of 97.10 ± 1.90% and a low irreversible fouling ratio (DRir) of 2.90%. The introduction of CA‐FSM‐16 on the surface of the PES membrane via the surface modification method was a potentially useful technology to fabricate a high‐performing TFN membrane for water treatment applications. [ABSTRACT FROM AUTHOR]

In today's technological landscape, advancing methods for producing conductive membranes that simplify and streamline the development of advanced interface materials is crucial. This study introduces a versatile and innovative method for fabricating superhydrophilic, conductive nanofibrous membranes based on the in situ synthesis of polypyrrole nanoparticles on poly(vinylidene fluoride‐co‐hexafluoropropylene) (PVDF‐HFP) electrospun fibers. The composite membranes morphologically exhibit a particle‐decorated nanofibrous configuration, with polypyrrole nanoparticles distributed along the individual fibers' surface. The nanoparticle‐nanofiber configuration shows distinctive properties; electrochemically, the electrospun mats demonstrate excellent inherent electrical conductivity, good cyclic and high electrochemical stability, and low resistance. Furthermore, the amphiphilic and superhydrophilic behavior, achieved through nanotopography, porosity and interactions between the intrinsically conductive polymer and the PVDF‐HFP fibers, enables efficient uptake of polar and nonpolar analytes. The membranes also demonstrate good in vitro cell viability of both murine and human fibroblasts. Given its efficient interaction with liquids and omnidirectional 360‐degree conductivity, this material emerges as an excellent candidate for use as a biocompatible, multifunctional interface layer. The produced nanoparticle‐nanofibrous membrane materials offer a promising platform for interface applications, featuring enhanced spatiotemporal configurations and wide‐ranging applicability. [ABSTRACT FROM AUTHOR]

The cell membrane not only serves as the boundary between the cell's interior and the external environment but also plays a crucial role in regulating fundamental cellular behaviours. Interfacial membranization of membraneless coacervates, formed through liquid-liquid phase separation (LLPS), represents a reliable approach to constructing hierarchical cell-like entities known as protocells. In this study, we demonstrate the capability to modulate the interfacial membrane fluidity and thickness of dextran-bound coacervate protocells by adjusting the molecular weight of dextran or utilizing dextranase-catalyzed hydrolysis. This modulation allows for rational control over colloidal stability, interfacial molecular transport and cell-protocell interactions. Our work opens a new avenue for surface engineering of coacervate protocells, enabling the establishment of cell-mimicking structures and behaviours. Membranization of coacervate microdroplets can stabilize coacervates and enable the construction of hierarchical protocells by using various interfacial layers. Here, the authors demonstrate the modulation of interfacial membrane fluidity and thickness of dextran-bound coacervate protocells by adjusting the molecular weight of dextran or through enzymatic hydrolysis, achieving control over colloidal stability, interfacial molecular transport and cell-protocell interactions. [ABSTRACT FROM AUTHOR]