Graphene Oxide Composite Membranes Research Articles

Effect of Plasma pretreatment and Graphene oxide ratios on the transport properties of PVA/PVP membranes for fuel cells

In this study, a novel proton-conducting polymer electrolyte membrane based on a mixture of polyvinyl alcohol (PVA)/polyvinyl pyrrolidone (PVP) (1:1) mixed with different ratios of graphene oxide (GO) and plasma-treated was successfully synthesized. Dielectric barrier dielectric (DBD) plasma was used to treat the prepared samples at various dose rates (2, 4, 6, 7, 8, and 9 min) and at fixed power input (2 kV, 50 kHz). The treated samples (PVA/PVP:GO wt%) were soaked in a solution of styrene and tetrahydrofuran (70:30 wt%) with 5 × 10−3 g of benzoyl peroxide as an initiator in an oven at 60 °C for 12 h and then sulfonated to create protonic membranes (PVA/PVP-g-PSSA:GO). The impacts of graphene oxide (GO) on the physical, chemical, and electrochemical properties of plasma-treated PVA/PVP-g-PSSA:x wt% GO membranes (x = 0, 0.1, 0.2, and 0.3) were investigated using different techniques. SEM results showed a better dispersion of nanocomposite-prepared membranes; whereas the AFM results showed an increase in total roughness with increasing the content of GO. FTIR spectra provide more information about the structural variation arising from the grafting and sulfonation processes to confirm their occurrence. The X-ray diffraction pattern showed that the PVA/PVP-g-PSSA:x wt% GO composite is semi-crystalline. As the level of GO mixing rises, the crystallinity of the mixes decreases. According to the TGA curve, the PVA/PVP-g-PSSA:x wt% GO membranes are chemically stable up to 180 °C which is suitable for proton exchange membrane fuel cells. Water uptake (WU) was also measured and found to decrease from 87.6 to 63.3% at equilibrium with increasing GO content. Ion exchange capacity (IEC) was calculated, and the maximum IEC value was 1.91 meq/g for the PVA/PVP-g-PSSA: 0.3 wt% GO composite membrane. At room temperature, the maximum proton conductivity was 98.9 mS/cm for PVA/PVP-g-PSSA: 0.3 wt% GO membrane. In addition, the same sample recorded a methanol permeability of 1.03 × 10−7 cm2/s, which is much less than that of Nafion NR-212 (1.63 × 10−6 cm2/s). These results imply potential applications for modified polyelectrolytic membranes in fuel cell technology.

Enhancing stability and ionic sieving efficiencies of GO membranes via copper ion crosslinking and tannic acid intercalation

Graphene oxide (GO) membranes have exhibited excellent molecular sieving properties in several areas, such as water treatment and gas separation, but unsatisfactory permeability and/or selectivity for ionic separation. Meanwhile, the instability of pure GO membranes in acidic solution has significantly impeded the ionic sieving applications. In this study, a kind of GO composite membranes (GO-Cu-TAa) with exceptional aqueous stability and superior ionic sieving properties are successfully prepared by employing a unique natural deposition strategy to introduce copper ions and tannic acid (TA). Based on the synergistic effect of the two cross-linking agents of copper ion and TA, the structural stability and ionic sieving performance of GO-Cu-TAa membranes are obviously enhanced. The resultant membrane with 20% TA loading displays excellent ionic sieving performance in a mixed solution containing K+, Mg2+ and Cr3+ three metal cations, and the selectivities of K+/Mg2+ and K+/Cr3+ are 46.43 and 185.32, respectively. Especially, the permeation rate of K+ ion reaches up to 0.75 mol m-2 h-1. Meanwhile, the ionic sieving property of such GO membranes possesses outstanding reusability and long-term stability. Such a membrane can also effectively separate mono-/multivalent metal cations from the mixed solution contained of the nine metal cations. The selectivities of monovalent/divalent metal cations (such as K+/Pb2+, K+/Ca2+, K+/Mg2+) are as high as 7.69–51.49, and those of monovalent/trivalent metal cations (such as K+/Fe3+, K+/Cr3+, K+/Al3+) are as high as 247.62–346.67. These results indicate that the GO-Cu-TAa membranes fabricated by the method of natural deposition strategy are expected to be used in the practical applications of lithium extraction from Salt Lake and wastewater purification, etc.

LEGO® brick-inspired ultra-stable and rapid transport 2D membrane for fast water purification

Inspired by the modular homogenization and interlocking structure concepts of LEGO® bricks, we developed high-performance graphene oxide composite nanofiltration membranes using the subject–object recognition effect.

Highly efficient mica-incorporated graphene oxide-based membranes for water purification and desalination.

Graphene oxide (GO) has become the most attractive material for membrane technology owing to its potential application as a nanofiller in water treatment, purification, and desalination. In this study, we incorporated mica as a cross-linking reagent to increase the interlayer spacing and stability of GO sheets and fabricated a mica/GO (MGO) membrane for the first time. The MGO membrane (260 ± 10 nm) exhibits 100% rejection for biomolecules such as tannic acid (TA) and bovine serum albumin (BSA) and >99% rejection for multiple probe molecules, such as methylene blue, methyl orange, congo red, and rhodamine B. The high rejection of membranes can be attributed to the surface interaction of mica with GO nanosheets through covalent interaction, which enhances the stability and separation efficiency of the membranes for probe ions and molecules. This ultrathin MGO membrane also exhibits much better water permeability at 870 ± 5 L m-2 h-1 bar-1, which is 10-100 times greater than that reported for pure GO and GO-based composite membranes. Additionally, the membrane shows high rejection for salt ions (70%). Furthermore, the stability of the MGO membranes was evaluated under various conditions, and the membranes demonstrated remarkable stability for up to 60 days in a neutral environment.

A novel strategy for retarding membrane wetting under electrical field: Embedding silver nanowires into UiO-66-NH2/graphene oxide composite thin membrane

Membrane distillation (MD) is a promising desalination technology that combines traditional distillation processes with membrane separation technology, but when the feed solution contains amphiphilic substances such as surfactant, the hydrophobic membrane is prone to being wetting, which hinders its widespread application. In this study, a novel Janus membrane was developed by embedding Zr-MOF and silver nanowires into the modified graphene oxide composite membrane to improve its separation performance, and the effect of high-concentration SDS on the membrane performance was studied. The experimental results showed that the conductive membrane exhibited excellent performance when powered on for 5 min every 2.5 h under 2 V voltage. The flux stabilized at 19.6 L/(m2h) with a desalination rate up to 99.9 % and no obvious signs of membrane wetting. It was found that the effect of electric field caused a negative charge on the membrane surface, forming a charge repulsion force with the SDS. Simultaneously, intermittent electrical flotation can effectively remove SDS that has accumulated on the membrane surface, thus achieving efficient and stable operation of MD system. Moreover, a machine learning approach with Catboost was applied to predict and unveil the complex effects on membrane performance, providing a deep insight to treat wastewater containing surfactant.

The potential of nano graphene oxide and chlorhexidine composite membranes for use as a surface layer in functionally graded membranes for periodontal lesions

Membranes have been used for treating periodontal defects and play a crucial role in guided bone regeneration applications. Nano graphene oxide have been exploited in tissue engineering due to its biomechanical properties. Its composite formulations with hydroxyapatite and chitosan with controlled degradation could aid in becoming part of a surface layer in a functionally graded membrane. The aim of the study was to synthesize chitosan and composite formulations of nano graphene oxide, hydroxyapatite and chlorhexidine digluconate using solvent casting technique and to characterize the physiochemical, mechanical, water vapor transmission rate (barrier), degradation and antimicrobial potential of the membranes. Altogether four different membranes were prepared (CH, CCG, 3511 and 3322). Results revealed the chemical interactions of hydroxyapatite, chitosan and nanographene oxide due to inter and intra molecular hydrogen bonding. The tensile strength of 3322 (33.72 ± 6.3 MPa) and 3511 (32.06 ± 5.4 MPa) was higher than CH (27.46 ± 9.6 MPa). CCG showed the lowest water vapor transmission rate (0.23 ± 0.01 g/h.m2) but the highest weight loss at day 14 (76.6 %). 3511 showed a higher drug release after 72 h (55.6 %) Significant biofilm growth inhibition was observed for all membranes. 3511 showed complete inhibition against A. actinomycetemcomitans. Detailed characterization of the synthesized membranes revealed that 3511 composite membrane proved to be a promising candidate for use as a surface layer of membranes for guided bone regeneration of periodontal lesions.Graphical

Highly Efficient Arginine Intercalated Graphene Oxide Composite Membranes for Water Desalination.

Graphene oxide-based composite membranes have received enormous attention for highly efficient water desalination. Herein, we prepare arginine/graphene oxide (Arg/GO) composite membranes by surface functionalizing GO nanosheets with arginine amino acid. Arginine has a unique combination of hydroxyl and amino functional groups that cross-link GO nanosheets through hydrogen bonding and electrostatic interactions. The as-prepared Arg@GO composite membranes with different thicknesses are used to separate the salt and dye molecules. The 900-nm-thick Arg@GO composite membrane shows high rejection of 98% for NaCl and 99.8% for MgCl2, Ni(NO3)2, and Pb(NO3)2 with good water permeance. Such a membrane also shows a high separation efficiency (100%) for methylene blue, rhodamine B, and Evans blue dyes. At the same time, the ultrathin Arg@GO composite membrane (220 ± 10 nm) exhibits high water permeance of up to 2100 ± 10 L m-2 h-1 bar-1. Furthermore, the 900-nm-thick Arg@GO composite membrane is stable in an aqueous environment for 40 days with significantly less swelling. Therefore, these membranes can be utilized in future desalination and separation applications.

Ethyl cellulose–graphene oxide composite dense membranes: Kinetic and thermodynamic studies of dye adsorption

Graphene oxide (GO) is extensively used in dye adsorption from wastewater. Polymer–GO composite membranes exhibits improved surface wettability and dye adsorption capacity. In this study, ethyl cellulose (EC)–GO nanocomposite dense membranes (EG membranes) are prepared by the solvent casting method. The morphology and physicochemical properties of the developed nanocomposite membranes are characterized using field emission scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction studies, thermogravimetric analysis, static contact angle measurements, and UV–visible spectroscopy. The derivative thermogravimetry curves indicate the complete degradation of the composites below [Formula: see text]C. The results confirm the homogeneous dispersion of GO in the EC matrix. The addition of GO to the EC matrix leads to a remarkable increase in surface wettability which decreases the contact angle to [Formula: see text] for the membrane with a 0.7% addition of GO. The prepared membranes are used for the separation of methylene blue from water. The adsorption properties of the prepared membranes are found to be varying in accordance with the contact angle values. The equilibrium data fit well for the Langmuir model and the adsorption follows pseudo-second-order kinetics.

Multiscale carbon - Based ion channel fiber membrane for efficient osmotic energy capture

The green energy generated by salinity gradient at the river-sea junction can be captured by Reverse Electrodialysis (RED) technology. The ion migration in the energy conversion process occurs in the narrow ion channel inside the permeable membrane of the core component. In practical applications, membrane used for osmotic energy conversion needs to meet the necessary conditions such as effective nano-channels, sufficient surface charges, large-scale preparation and stable energy output. It is challenging to achieve all of these requirement at the same time and calls for an exquisite design of the permeable membrane. Herein, we demonstrate an ion channel membrane regulated by a carbon-based membrane with hierarchical channels for efficient osmotic energy conversion. Porous carbon (PC) nanosheets with high porosity and high modulus are filled into carbon nanofibers (CNFS)/graphene oxide (GO) composite membrane, increasing ion transport channels and providing additional space charge to improve ion selectivity. The power output from PC@GO/CNFs membranes modified with nano-porous carbon reaches 4.3 W·m−2. In addition, the ion-selective membrane obtained by this strategy has the advantages of simple process, adjustable area and good stability. This simple strategy is one of the feasible paths for infiltration to be collected effectively. Ion-selective membrane is the key component for osmotic energy conversion.

Facile Fabrication of a Free-Standing Magnesium Oxide-Graphene Oxide Functionalized Membrane: A Robust and Efficient Material for the Removal of Pollutants from Aqueous Matrices

Environmental pollution significantly challenges human health, ecosystems, and the planet’s sustainability. Widespread air, water, and soil contamination from various pollutants requires effective and sustainable solutions to reduce or eliminate pollution and its impacts. In this work, we designed novel magnesium oxide and graphene oxide (MgO@GO) composite free-standing membranes for nanofiltration. The membranes were characterized with the help of Fourier-transform infrared spectroscopy, X-ray diffraction, field-emission scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Further, free-standing MgO@GO composite membranes with different thicknesses were used to measure the water permeance. 410 nm-thick membranes showed high water permeance up to 480 ± 5 Lm−2 h−1 bar−1. Further, the rejection efficiency of the membrane was measured against NaCl, CaCl2, Pb(NO3)2, CdCl2, and amoxicillin. The MgO@GO membrane (410 ± 10 nm) showed 100% rejection for amoxicillin and 99% for Pb(NO3)2, respectively. Additionally, the membranes were stable under acidic and neutral conditions for approximately ∼80 days and may used on an industrial scale to ensure water is clean and free from harmful substances.

Fabrication of 1D/2D ATP/GO-COOH membrane with low-resistance transport pathways for highly efficient separation of oil-in-water emulsion

Attapulgite/carbonylated graphene oxide (ATP/GO-COOH) composite membranes have been successfully prepared by vacuum-assisted filtration of an aqueous ATP/GO-COOH dispersion on a microfiltration substrate. Due to the interaction between the OH groups of ATPs and COOH groups of GO-COOH, ATP rods showed excellent compatibility with GO-COOH nanosheets, and the ATP mass fraction was significantly improved. The large amount of ATP can establish a fast transport channel for the diffusion of water molecules in the composite membrane. As a result, the optimum membrane gave a permeation flux with 13582 L/(m2 h), which is significantly higher than that of the pure GO-COOH membrane (2281 L/(m2 h)). In addition, the underwater superoleophobic properties of the ATP/GO-COOH composite membrane enable it to have a low oil-adhesive water/membrane interfaces. The ATP/GO-COOH composite membrane showed good separation and separation stability for oil-in-water emulsion systems with different concentrations, pH, and oil types.

Improving permeability and fouling resistance of GO hydrophilic/hydrophobic Janus membrane by polyether amine crosslinking for membrane distillation of dye wastewater

Graphene oxide (GO) modification is promising to increase vapor flux and antifouling properties of hydrophobic membranes in membrane distillation for wastewater treatment. However, the acid bonding of GO with dyes impedes its wide application in dye wastewater treatment. In this study, polyether amine D400 was used to modify hydrophilic GO layer of Janus membrane. The GD3/PTFE composite membrane (GO and D400 mass ratio of 1:2) demonstrated the best water flux and antifouling performance for methyl orange (MO) containing 3.5 wt% NaCl. The flux was increased by 170.3%− 228.9% compared to PTFE pristine membrane and the flux decline due to fouling was decreased by 41.3%− 60.8% to GO/PTFE membrane. The observed increase in the longitudinal thermal conductivity of the cross-linked GO layer suggests that the enhanced permeability is attributed to improved heat transfer resulting from the higher density of GO nanosheets. Acid bonding of GO layer with dye molecular is weakened and electrostatic repulsion is also increased, leading to the excellent antifouling performance. This study indicate that polyether amine crosslinking is promising method for modification of GO composite membrane for dye wastewater treatment.

Sub-20 nm ultrathin perfluorosulfonic acid-grafted graphene oxide composite membranes for vanadium redox flow batteries

Perfluorosulfonic acid (PFSA) membranes, such as Nafion, are widely used in vanadium redox flow batteries (VRFBs) because of their high proton conduction through the ion channels and excellent chemical stability. However, the high vanadium permeability of PFSA membranes induced by the randomly interconnected channels limits efficient cell operation. In this work, we demonstrate a sub-20 nm ultrathin PFSA-grafted graphene oxide/PFSA (PFSA-g-GO/PFSA) composite membrane with highly aligned ion channel morphology, which results in a 100-fold improvement in proton/vanadium ion selectivity compared to 25 μm-thick Nafion 211. In addition, the PFSA-g-GO nanosheets physically reinforce the ultrathin membrane while enabling the proton transport through the grafted PFSA ionomers, leading to stable cell operation at overall current densities from 40 to 200 mA cm−2. Especially, at a high current density of 200 mA cm−2, the PFSA-g-GO/PFSA composite membrane shows an energy efficiency (EE) of 78%, which is higher than that of Nafion 211, indicating its potential as an ion-selective membrane for VRFB.

Interfacial interaction of graphene oxide with montmorillonite in tailoring the structure and proton transport phenomena of alginate/PVA membrane for DMFC applications

AbstractPolymer electrolyte membrane that has high proton conductivity and low methanol permeability are necessary for direct methanol fuel cells (DMFCs). A sodium alginate (SA)/polyvinyl alcohol (PVA)/montmorillonite (MMT)/graphene oxide (GO) quaternary composite membrane was effectively developed in this study. The homogeneous distribution of MMT and GO nanosheets in the SA/PVA/MMT/GO composite membrane was exhibited by scanning electron microscopy (SEM). Intriguingly, it has been established that the SA/PVA membrane contains chemical crosslinks between MMT and GO, which significantly contribute to the rise in proton conductivity. The SA/PVA/MMT/GO hybrid membrane has minimum loss modulus of 47.91% and storage modulus of up to 2.689 × 109 Pa, which are 3.8 times greater than those of SA/PVA‐MMT membrane without GO. This value indicates the viscosity and elasticity of the produced membrane. The quaternary composite membrane also exhibits outstanding oxidative stability and methanol barrier characteristics. The methanol permeability of SA/PVA/MMT/GO films 0.524 × 10−9 cm2 s−1, with methanol absorption as low as 9.72%. The best membrane performs at a high‐power density (1.761 mW/cm2) of DMFC at a GO content of 1.3 wt% because it obtains the maximum selectivity value (7.0529 × 106 S scm−3). Future commercial membranes may be replaced by the innovative quaternary membrane created in this work, which has significant potential.

Modificationof ceramic-supported graphene oxide composite membranes to dedicate them the dry state CO2 permselectivity

Graphene oxide composite membranes have revealed great potential for gas separation tasks. These membranes' structural integrity and stability and also separation performance considerably depend on their support characteristics. This work studies the effect of modification of the GO membranes’ support by coating them with some γ-alumina interlayers to obtain defect-free graphene oxide composite membranes by filtration method. Also, graphene oxide nanosheets were functionalized with ethylenediamine to improve their CO2 permselectivity via the promotion of the adsorption selectivity portion. The morphology and microstructure of the synthesized materials and the prepared membranes were characterized by FTIR, SEM and FESEM, AFM, XRD, DLS, and BET analysis. The results confirmed successful GO nanosheet preparation. CO2 and CH4 permeances through the prepared membranes were measured at 30 °C and a pressure range of 0.5–3 barg. Ideal CO2/CH4 selectivity and CO2 permeance of the functionalized graphene oxide coated on the modified support at 2.5 barg and 30 °C under the dry state, were inverted to 1.33 in favor of CO2 and increased by nearly three times, respectively, compared with those of graphene oxide composite membrane coated on the unmodified support.

Preparation of antibacterial PHBV/GO nanocomposite membranes via electrospinning

Poly(3-hydroxybutyrate-co-3-hydroxypentanoate) (PHBV)/graphene oxide (GO) composite membranes were electrospun with an aim at fabricating antibacterial nanofibrous scaffolds for tissue engineering application. Randomly and aligned oriented PHBV/GO fibrous membrane were prepared by controlling the mixed solvent, GO concentration and process parameters, and their effect on the morphology and structure of the membranes was investigated. When 10 wt% GO nanosheets was incorporated into the composite spinning dope, PHBV/GO membrane presented a 18.7 MPa breaking strength and 5.51 × 102 MPa tensile modulus, much greater than 14.3 MPa and 1.76 × 102 MPa of PHBV membrane. Colonies forming units of E.coli and S.aureus reduced by 81.7% and 71.8% for randomly oriented PHBV/GO, and 84.2% and 73.4% for aligned oriented PHBV/GO when compared to PHBV membrane. The development of bacterial biofilm on PHBV/GO membrane reduced greatly when incorporating 5–10 wt% GO. The antibacterial PHBV/GO membranes with better mechanical properties showed great promise for further studies on bone tissue repair.

Constructing high-performance GO membrane with pore-adjustable polymer nanoparticles

Desalination of textile wastewater is an effective measure to reduce environmental pollution and realize resource reuse. Graphene oxide (GO) membrane is regarded as one of the first choices for textile wastewater desalination due to its chemical resistance, strong mechanical properties, and adjustable interlayer channels. Here, we propose a polyaniline (PANI) particle incorporation strategy and use the dedoping effect of polyaniline to provide an additional permeation pathway through one-step alkali treatment to accelerate water molecule transport. Polyaniline (PANI) doped with polystyrene sulfonic acid (PSS) nanoparticles were synthesized and incorporated into GO membranes, followed by crosslinking of glutaraldehyde (GA) for stability and alkali treatment for more porosity generation. The as-prepared BGO/PANI-PSS membrane with 30% PANI-PSS addition displayed a flux of 70.4 LMH/bar, 99.3%, and 4.8% rejection for Congo red and NaCl, respectively, exhibiting 5.9 times higher permeability than that of GO membrane with similar dye rejection. This work provides a facile strategy for designing GO composite membranes for dye/salt separation.

Permeation Properties of Water Vapor through Graphene Oxide/Polymer Substrate Composite Membranes.

Graphene oxide (GO) has attracted attention as an excellent membrane material for water treatment and desalination owing to its high mechanical strength, hydrophilicity, and permeability. In this study, composite membranes were prepared by coating GO on various polymeric porous substrates (polyethersulfone, cellulose ester, and polytetrafluoroethylene) using suction filtration and casting methods. The composite membranes were used for dehumidification, that is, water vapor separation in the gas phase. GO layers were successfully prepared via filtration rather than casting, irrespective of the type of polymeric substrate used. The dehumidification composite membranes with a GO layer thickness of less than 100 nm showed a water permeance greater than 1.0 × 10-6 mol/(m2 s Pa) and a H2O/N2 separation factor higher than 104 at 25 °C and 90-100% humidity. The GO composite membranes were fabricated in a reproducible manner and showed stable performance as a function of time. Furthermore, the membranes maintained high permeance and selectivity at 80°C, indicating that it is useful as a water vapor separation membrane.

Assessment of innovative graphene oxide composite membranes for the improvement of direct methanol fuel cells performance

The main objective of the study was to verify potential of GO-PEM and its best effective usage in a Direct Methanol Fuel Cells (DMFC) application so investigating the effect of this filler on cell performance, varying several operating conditions, without affecting the mechanical and electric properties of the baseline PEM. In this work, GO was added to the Nafion polymer using a weight percentage varying from 0.5 to 1.5%. The present analysis showed that the GO-membranes have higher tensile strength, greater water, and methanol uptake. It was also demonstrated that the presence of carbon compounds slightly reduced the proton conductivity suggesting that an optimal GO-content must be determined. Comparing several physical and electrochemical properties, we concluded that the 1 wt. %GO-loading PEM represents the most effective solution. Later, the advantages of adopting GO-PEMs in DMFCs were also assessed. A comparative analysis of a GO-DMFC and a standard DMFC was carried out by changing the relevant control parameters, such as anode flow rate, temperature, and methanol concentration obtaining that: a) the GO-DMFC performance enhanced when increasing the temperature and the anode flow rate; b) an increase in methanol concentration had a beneficial effect on DMFC performance only up to a peak value after that a rapid reduction was noticed. Optimal conditions were obtained for an anode flow rate of 7 µl min−1, a temperature of 60 °C and a 1 M methanol concentration.

A novel UiO-66-NH2/graphene oxide composite thin membrane for retarding membrane wetting in membrane distillation

Membrane distillation (MD) is considered an emerging desalination technology. However, the presence of surfactants allows liquid to penetrate the membrane, resulting in membrane wetting, which hinders the commercialization of MD. In this study, we use very few modified materials to prepare novel Janus thin membranes that immobilize modified materials (graphene oxide (GO) and UiO-66-NH2) on polytetrafluoroethylene (PTFE) hydrophobic base membranes via crosslinkers. The composite thin membrane properties with eight different ratios and contents of GO and UiO-66-NH2 were fabricated and tested by a feed solution of sodium chloride containing a high concentration of sodium dodecyl sulfate. An optimal ratio of Janus membrane with high flux without affecting the effluent water quality was obtained. The Janus membrane exhibited excellent anti-wetting properties compared to the original PTFE membrane. A desalination rate of up to 99.9% was still available even under 48 h of long-term operating conditions by maintaining a flux of approximately 21.2 L/(m2·h). The anti-wetting mechanism of this membrane was further confirmed by the modified XDLVO model. It suggested that the novel Janus membrane could be a highly promising substitute to the MD process for the resource-based treatment of surfactant-containing wastewater, which played an important role in promoting its application.