One-step Sb(III) decontamination using a bifunctional photoelectrochemical filter

Facile synthesis of δ-MnO2 biotemplated by waste tobacco stem-silks for enhanced removal of Sb(III)

The elimination of antimony pollution has attracted increasing concerns because of its high toxicity to human health and the natural environment. In this work, biomimetic δ-MnO2 was synthesized by using waste tobacco stem-silks as biotemplate (Bio-δ-MnO2) and used in the capture of Sb(III)from aqueous solution. The tobacco stem-silks not only provided unique wrinkled morphologies but also contained carbon element self-doped into the resulting samples. The maximum Sb(III) adsorption capacity reached 763.4 mg∙g -1, which is 2.06 times higher than δ-MnO2 without template (370.0 mg∙g -1), 4.53 times than tobacco stem-silks carbon (168.5 mg∙g -1), and 10.39 times than commercial MnO2 (73.5 mg∙g -1), respectively. The isotherm and kinetic studies indicated that the adsorption behavior was consistent with the Langmuir isotherm model and the pseudo-second-order kinetic equation. As far as we are aware, the adsorption capacity of Bio-δ-MnO2 is much higher than that of most Sb(III) adsorbents. FT-IR, XPS, SEM, XRD, and Zeta potential analyses showed that the main mechanism for the adsorption of Sb(III) by Bio-δ-MnO2 includes electrostatic attraction, surface complexation, and redox. Overall, this study provides a new sustainable way to convert agricultural wastes to more valuable products such as biomimetic adsorbent for Sb(III) removal in addition to conventional activated carbon and biochar.

Electrochemical CNT filter functionalized with metal-organic framework for one-step antimonite decontamination

Currently, there is a lack of advanced nanotechnology designed to efficiently remove antimony (Sb) from contaminated water systems. Sb most commonly appears as antimonite (Sb(III)) or as the anion antimonate (Sb(V)). Sb(III) is approximately ten times more toxic than Sb(V), and Sb(III) is also harder to eliminate because of its motility and charge neutrality. The work presented here developed an electrochemical filtration technology for the direct elimination of Sb(III) from contaminated water. The primary components of the filtration system are an electroactive carbon nanotube (CNT) membrane that are functionalized with the Sb-specific UiO-66(Zr), an organometallic framework. In an electric field, the UiO-66(Zr)/CNT nanohybrid filter enabled in situ transformation of Sb(III) to less harmful Sb(V). The Sb(V) was then effectively adsorbed by the UiO-66(Zr). The removal efficiency (90.5%) and rate constant (k₁ = 0.0272 min^-1) toward Sb(III) removal was 1.3 and 1.4 times greater than that of CNT filter. The filter's abundance of available adsorption sites, flow-through construction, and electrochemical activity combined to rapidly remove Sb(III) from water. The underlying functioning of the nanohybrid filter was determined with a series of process experiments and structural characterizations. The filter was effective over a broad range of pH values and in a variety of complex aqueous environments. Once loaded with Sb, the UiO-66(Zr)/CNT filter could be washed with a dilute NaOH solution to efficiently refresh its activity. The results of this work offer a direct, efficient strategy that integrates nanotechnology, electrochemistry, and membrane separation to remove antimony and potentially other heavy metals from contaminated water.

Volatile organic compound removal by post plasma-catalysis over porous TiO2 with enriched oxygen vacancies in a dielectric barrier discharge reactor

Non-thermal plasma (NTP) degradation of volatile organic compounds (VOCs) into CO₂ and H₂O is a promising strategy for addressing ever-growing environment pollution. However, its practical implementation is hindered by low conversion efficiency and emissions of noxious by-products. Herein, an advanced low-oxygen-pressure calcination process is developed to fine-tune the oxygen vacancy concentration of MOF-derived TiO₂ nanocrystals. Vo-poor and Vo-rich TiO₂ catalysts were placed in the back of an NTP reactor to convert harmful ozone molecules into ROS that decompose VOCs via heterogeneous catalytic ozonation processes. The results indicate that Vo-TiO₂-5/NTP with the highest Vo concentration exhibited superior catalytic activity in the degradation of toluene compared to NTP-only and TiO₂/NTP, achieving a maximum 96% elimination efficiency and 76% CO_x selectivity at an SIE of 540 J L^-1. Mechanistic analysis reveals that the ¹O₂, ˙O₂^- and ˙OH species derived from the activation of O₃ molecules on Vo sites contribute to the decomposition of toluene over the Vo-rich TiO₂ surface. With the aid of advanced characterization and density functional theory calculations, the roles of oxygen vacancies in manipulating the synergistic capability of post-NTP systems were explored, and were attributed to increased O₃ adsorption ability and enhanced charge transfer dynamics. This work presents novel insights into the design of high-efficiency NTP catalysts structured with active Vo sites.

Capacity of Nerium oleander to Phytoremediate Sb-Contaminated Soils Assisted by Organic Acids and Oxygen Nanobubbles

Antimony (Sb) is considered to be a toxic metalloid of increasing prevalence in the environment. Although several phytoremediation studies have been conducted, research regarding the mechanisms of Sb accumulation and translocation within plants remains limited. In this study, soil from a shooting range was collected and spiked with an initial Sb(III) concentration of 50 mg/kg. A pot experiment was conducted to investigate whether Nerium oleander could accumulate Sb in the root and further translocate it to the aboveground tissue. Biostimulation of the soil was performed by the addition of organic acids (OAs), consisting of citric, ascorbic, and oxalic acid at low (7 mmol/kg) or high (70 mmol/kg) concentrations. The impact of irrigation with water supplemented with oxygen nanobubbles (O₂NBs) was also investigated. The results demonstrate that there was a loss in plant growth in all treatments and the presence of OAs and O₂NBs assisted the plant to maintain the water content at the level close to the control. The plant was not affected with regards to chlorophyll content in all treatments, while the antioxidant enzyme activity of guaiacol peroxidase (GPOD) in the roots was found to be significantly higher in the presence of Sb. Results revealed that Sb accumulation was greater in the treatment with the highest OAs concentration, with a bioconcentration factor greater than 1.0. The translocation of Sb for every treatment was very low, confirming that N. oleander plant cannot transfer Sb from the root to the shoots. A higher amount of Sb was accumulated in the plants that were irrigated with the O₂NBs, although the translocation of Sb was not increased. The present study provides evidence for the phytoremediation capacity of N. oleander to bioaccumulate Sb when assisted by biostimulation with OAs.

Urea-oxidation-assisted electrochemical water splitting for hydrogen production on a bifunctional heterostructure transition metal phosphides combining metal-organic frameworks

Electrocatalyzed urea-assisted wastewater splitting is a promising approach for sustainable hydrogen production. However, the lack of cost-efficient electrocatalysts hinders its practical application. Herein, bimetal phosphide (NiCoP_x) nanowire arrays decorated with ultrathin NiFeCo metal-organic framework (NiFeCo-MOF) nanosheets on porous nickel foam (NF) were designed for urea-assisted wastewater splitting. The core-shell NiCoP_x@NiFeCo-MOF hybrids were prepared via successive hydrothermal, gas-phase phosphorization and hydrothermal strategies. Encouragingly, the novel NiCoP_x@NiFeCo-MOF/NF electrode served as an excellent bifunctional electrocatalyst for both the cathodic hydrogen evolution reaction (HER) and the anodic urea oxidation reaction (UOR) in urea-assisted water splitting, which merely required an overpotential of 44 mV to deliver a current density of 10 mA cm^-2 for HER and a voltage of 1.37 V to deliver a current density of 100 mA cm^-2 for UOR in 1.0 M KOH + 0.5 M urea. Benefiting from the highly exposed electroactive sites in exquisite three-dimensional (3D) hierarchical structure, multicomponent synergistic effect, accelerated electron transfer, easy electrolyte access and diffusion of released gas bubbles, the as-fabricated NiCoP_x@NiFeCo-MOF/NF exhibited outstanding electrocatalytic performance. The mechanism of water splitting was elucidated by density functional theory calculations. Interestingly, NiFeCo-MOF possessed optimized COO* adsorption ability on Ni sites that were beneficial to UOR intermediates. More significantly, this work paves the way for the design and fabrication of bifunctional electrocatalysts for urea-containing wastewater treatment and sustainable hydrogen production.

A critical review on classifications, characteristics, and applications of electrically conductive membranes for toxic pollutant removal from water: Comparison between composite and inorganic electrically conductive membranes

Research efforts have recently been directed at developing electrically conductive membranes (EMs) for pressure-driven membrane separation processes to remove effectively the highly toxic pollutants from water. EMs serve as both the filter and the electrode during filtration. With the assistance of a power supply, EMs can considerably improve the toxic pollutant removal efficiency and even realize chemical degradation to reduce their toxicity. Organic-inorganic composite EMs and inorganic EMs show remarkable differences in characteristics, removal mechanisms, and application situations. Understanding their differences is highly important to guide the future design of EMs for specific pollutant removal from water. However, reviews concerning the differences between composite and inorganic EMs are still lacking. In this review, we summarize the classifications, fabrication techniques, and characteristics of composite and inorganic EMs. We also elaborate on the removal mechanisms and performances of EMs toward recalcitrant organic pollutants and toxic inorganic ions in water. The comparison between composite and inorganic EMs is emphasized particularly in terms of the membrane characteristics (pore size, permeability, and electrical conductivity), application situations, and underlying removal mechanisms. Finally, the energy consumption and durability of EMs are evaluated, and future perspectives are presented.

Trivalent antimony removal using carbonaceous nanomaterial loaded with zero-valent bimetal (iron/copper) and their effect on seed growth

As rapid industrial and social growth, antimony mines are the overexploited, leading to the accumulation of trivalent antimony in the aquatic environment near smelters, which harm human health. To eradicate trivalent antimony from water, an innovative nanomaterial in the form of sludge biochar loaded with zero-valent bimetal was synthesized using a liquid-phase reduction method. The adsorption performance of the nanomaterial for trivalent antimony was investigated based on a series of adsorption experiments using sludge biochar, nano zero-valent iron biochar, and nano zero-valent bimetal biochar. The results showed that the optimal adsorption performance of the three nanomaterials for trivalent antimony, considering the economic practicability, was highlighted at solution pH of 3 and 0.05 g of nanomaterial. Additionally, the maximum adsorption capacity of sludge biochar, nano zero-valent iron biochar, and nano zero-valent bimetal biochar is 3.89 mg g^-1 at 35 °C, 32.01 mg g^-1 at 25 °C, 50.96 mg g^-1 at 25 °C, respectively. The adsorption process of sludge biochar is endothermic, resulting in an increase in the adsorption capacity with increasing temperature, whereas the exothermic reaction contributes to decrease in the adsorption capacity at increasing temperature for the other two carbon nanomaterials. The inhibitory effect of coexisting ions was in the order: Al³⁺ > NH₄⁺ > Na⁺ > K⁺; CO₃^2- > CH₃COO^- > H₂PO₄^- > S^2-. Additionally, nanomaterials promoted seed germination and growth. Investigation of the adsorption mechanism using X-ray photoelectron spectroscopy showed that trivalent antimony was oxidised to pentavalent antimony, and Fe(III) was reduced to Fe(II). The formed primary battery formed by copper ions and iron acclerated electron transfer and improved the adsorption rate. This implied that trivalent antimony could be removed through the synergistic action of the adsorption behaviour and redox reaction. Therefore, the biochar loaded with the zero-valent bimetal serves as a pathway for eradicating trivalent antimony.

Peroxymonosulfate Activation by Photoelectroactive Nanohybrid Filter towards Effective Micropollutant Decontamination

Herein, we report and demonstrate a photoelectrochemical filtration system that enables the effective decontamination of micropollutants from water. The key to this system was a photoelectric–active nanohybrid filter consisting of a carbon nanotube (CNT) and MIL–101(Fe). Various advanced characterization techniques were employed to obtain detailed information on the microstructure, morphology, and defect states of the nanohybrid filter. The results suggest that both radical and nonradical pathways collectively contributed to the degradation of antibiotic tetracycline, a model refractory micropollutant. The underlying working mechanism was proposed based on solid experimental evidences. This study provides new insights into the effective removal of micropollutants from water by integrating state–of–the–art advanced oxidation and microfiltration techniques.

Ultrasonic-Assisted Synthesis of CdS/Microcrystalline Cellulose Nanocomposites With Enhanced Visible-Light-Driven Photocatalytic Degradation of MB and the Corresponding Mechanism Study

A simple and efficient ultrasonic-assisted approach was designed to synthesize CdS/microcrystalline cellulose (MCC) nanocomposite photocatalyst. The obtained products have been characterized by XRD, FE-SEM, TEM, UV-Vis DRS, and nitrogen adsorption isotherms. The results showed that the intimate contact of MCC and CdS is beneficial for enhancing the photocatalytic performance because heterojunction formation can efficiently promote the separation of photogenerated electrons and holes of the nanocomposite photocatalyst. By using 10% MCC coupled CdS, the decoloration rate of methylene blue (MB) in the solution under visible-light was increased nearly 50%. In addition, the reuse experiments confirmed that the CdS/MCC nanocomposite photocatalyst had outstanding cycle performance and durability. Mechanism study demonstrated that hydroxyl radicals, photogenerated holes and superoxide radicals were the active species in the photocatalytic oxidization degradation of MB.

Carbon nanotube filter functionalized with MIL-101(Fe) for enhanced flow-through electro-Fenton

Herein, an electrochemical carbon nanotubes (CNT) filter modified with MIL-101(Fe) has been designed for the electro-Fenton applications by serving as a functional flow-through electrode. Under an electric field, the hybrid filter enabled the in situ generation of H₂O₂via the two-electron oxygen reduction reaction, which promoted the production of HO by the accelerated Fe²⁺/Fe³⁺ cycling of MIL-101(Fe). It was observed that 93.2 ± 1.2% tetracycline and 69.0 ± 0.8% total organic carbon (TOC) were removed in 2 h under the optimized conditions. The electron paramagnetic resonance (EPR) analysis and radical scavenging experiments revealed that HO predominated the tetracycline degradation. As compared to the batch reactor, the performance of the proposed system was improved by 5.6 times owing to the convection-enhanced mass transport. The plausible working mechanism and degradation pathway were also subsequently proposed. The findings reported in this study provide a promising insight for the environmental remediation by integrating nanotechnology and Fenton chemistry.

Removal of antimonite (Sb(III)) from aqueous solution using a magnetic iron-modified carbon nanotubes (CNTs) composite: Experimental observations and governing mechanisms

In this study, a novel nanoscale iron oxide (FeO_x) modified carbon nanotubes composite (FeO_x@CNTs) was synthesized through a combined ball milling-hydrothermal two-step method and tested for aqueous Sb(III) removal efficiency and mechanisms. FeO_x nanoparticles was successfully loaded on the surface of CNTs through functional groups such as hydroxyl (-OH), C-H, and C-O to enhance the removal efficiency of Sb(III) through adsorption and surface complexation. At a dosage of 0.02 g, a FeCl₃·6H₂O-to-CNTs mass ratio of 3:1, and an initial solution pH of 6.3, the amount of Sb(III) removed by the prepared FeO_x@CNTs reached 172 mg/g, which was 42.9 times higher than that of the pristine CNTs (4.01 mg/g). Chemical adsorption and oxidation were the main removal mechanisms. At the equilibrium Sb(III) concentration of 6.08 mg/L, 6.56% of initial Sb(III) was adsorbed onto the surface of FeO_x@CNTs, and 81.3% of initial Sb(III) was oxidized to Sb(V) with lower toxicity. The pseudo-second-order kinetic model could better describe the adsorption of Sb(III) onto the FeO_x@CNTs composite, indicating that adsorption was mainly controlled by chemical sorption. In the adsorption isotherm equation, the Redlich-Peterson model provided a better fit of Sb(III) adsorption onto the FeO_x@CNTs composite than the Langmuir and Freundlich models, which further indicated that the adsorption process was a hybrid removal process dominated by chemical sorption. The presence of CO₃^2- slightly promoted the removal of Sb(III) from aqueous solution. The synthesized composite was magnetic and could be easily separated from the solution by an external magnetic field at the end of the sorption experiment. Based on these findings, the FeO_x@CNTs nanocomposite is expected to provide an environmentally-friendly adsorbent with a strong sorption capacity for remediating Sb(III) in water environments.

Insights into adsorptive removal of antimony contaminants: Functional materials, evaluation and prospective

The application of antimony containing compounds in the industry has generated considerable antimony contaminants, which requires to develop methods that are as efficient as possible to remove antimony from water in the view of human health. The adsorption is among the most high-efficiency and reliable purification methods for hazardous materials due to the simple operation, convenient recycling and low cost. Herein, this review systematically summarizes the functional materials that are used to adsorb antimony from water, including metal (oxides) based materials, carbon-based materials, MOFs and molecular sieves, layered double hydroxides, natural materials, and organic-inorganic hybrids. The iron-based adsorbents stand out among these adsorbents because of their excellent performance. Moreover, the interaction between antimony and different functional materials is discussed in detail, while the inner-sphere complexation, hydrogen bond as well as ligand exchange are the main impetus during antimony adsorption. In addition, the desorption methods in adsorbents recycling are also comprehensively summarized. Furthermore, we propose an adsorption capacity balanced evaluation function (ABEF) based on the reported results to evaluate the performance of the antimony adsorption materials for both Sb(III) and Sb(V), as antimony usually has two valence forms of Sb(III) and Sb(V) in wastewater. Another original insight in this review is that we put forward a potential application prospect for the antimony-containing waste adsorbents. The feasible future development includes the utilization of the recycled antimony-containing waste adsorbents in catalysis and energy storage, and this will provide a green and sustainable pathway for both antimony removal and resourization.

Antimony, a pollutant of emerging concern: A review on industrial sources and remediation technologies

Technologies for remediation of industrial effluents and natural sources contaminated with antimony - a pollutant of emerging concern - are just emerging. The complex speciation of antimony makes it challenging to devise effective remediation technologies. Antimony is used in several industrial applications and comes into the environment majorly through human induced activities such as antimony mining and other activities involving the use of various products containing antimony. Many researchers are working on the important task of developing methodologies to stop or limit the release of antimony into the environment through these activities. Antimony removal is an important requirement in nuclear industry as well due to the formation of its radioactive isotopes during power plant operations. Thus, better antimony remediation or removal techniques can have wider applications ranging from domestic water treatment and industrial effluent remediation to safe isolation of radioactive waste in the nuclear industry. Proper understanding of the problem is very important in designing the source appropriate remediation technique. Treatment methodologies needed for antimony effluents from antimony mining and smelting industries are different from antimony decontamination in nuclear reactors. The problem of antimony leaching from a polyethylene terephthalate bottle is very much different from the leaching of antimony from mining wastes. Each process necessitates custom-made treatment methodologies by taking into account various factors including the speciation and concentration. The current review is focused on this aspect. The review attempts to bring out a clear understanding on various industry specific sources of antimony pollution and the available antimony removal/remediation technologies.

Electrochemical recovery and high value-added reutilization of heavy metal ions from wastewater: Recent advances and future trends

Wastewater treatment for heavy metals is currently transitioning from pollution remediation towards resource recovery. As a controllable and environment-friendly method, electrochemical technologies have recently gained significant attention. However, there is a lack of systematic and goal oriented summarize of electrochemical metal recovery techniques, which has inhibited the optimized application of these methods. This review aims at recent advances in electrochemical metal recovery techniques, by comparing different electrochemical recovery methods, attempts to target recycling heavy metal resources with minimize energy consumption, boost recovery efficiency and realize the commercial application. In this review, different electrochemical recovery methods (including E-adsorption recovery, E-oxidation recovery, E-reduction recovery, and E-precipitation recovery) for recovering heavy metals are introduced, followed an analysis of their corresponding mechanisms, influencing factors, and recovery efficiencies. In addition, the mass transfer efficiency can be promoted further through optimizing electrodes and reactors, and multiple technologies (photo-electrochemical and sono-electrochemical) could to be used synergistically improve recovery efficiencies. Finally, the most promising directions for electrochemical recovery of heavy metals are discussed along with the challenges and future opportunities of electrochemical technology in recycling heavy metals from wastewater.

Surface modification of BiOBr/TiO2 by reduced AgBr for solar-driven PAHs degradation: Mechanism insight and application assessment

A novel solar active AgBr/BiOBr/TiO₂ catalyst was synthesized by a facile coprecipitation method for solar-driven water remediation. The synthesized material composed of flower-like TiO₂ nanoparticles loaded on BiOBr nanosheets and with homogeneous surface distributed Ag/AgBr nanoparticles. The internal electric field between BiOBr/TiO₂ heterojunction greatly facilitated the charge carrier migration; the introduction of narrow band gap semiconductors (AgBr and BiOBr) promoted the visible light adsorption; and the Ag/AgBr nanoparticles acted as photosensitizer to further improve the light utilization. The new material showed 7.6- and 4.0-times activity of pure TiO₂ and BiOBr under solar light, and the contribution of reactive species on anthracene degradation followed the order of h⁺ >O₂^•-> •OH. The degradation mechanism and pathway were proposed based on intermediates analysis and DFT calculation. The QSAR analysis revealed that the environmental risks of contaminants were greatly reduced during the photocatalysis process but some intermediates were still toxic. The high photocatalytic activity, stability and adaptability all indicated that this new material owns great application potential for cost-effective photocatalytic remediation of persistent organic contaminants under solar light.

Sea urchin-like FeOOH functionalized electrochemical CNT filter for one-step arsenite decontamination

Advanced nanotechnologies for efficient arsenic decontamination remain largely underdeveloped. The most abundant inorganic arsenic species are neutrally-charged arsenate, As(III), and negatively-charged arsenite, As(V). Compared with As(V), As(III) is 60 times more toxic and more difficult to remove due to high mobility. Herein, an electrochemical filtration system was rationally designed for one-step As(III) decontamination. The key to this technology is a functional electroactive carbon nanotube (CNT) filter functionalized with sea urchin-like FeOOH. With the assistance of electric field, CNT-FeOOH anodic filter can in situ transform As(III) to less toxic As(V) while passing through. Then, as-produced As(V) could be effectively sequestrated by FeOOH. The sufficient exposed sorption sites, flow-through design, and filter's electrochemical reactivity synergistically guaranteed a rapid arsenic removal kinetic. The underlying working mechanism was unveiled based on systematic experimental investigations and theoretical calculations. The system efficacy can be adapted across a wide pH range and environmental matrixes. Exhausted CNT-FeOOH filters could be effectively regenerated by chemical washing with diluted NaOH solution. Outcomes of the present study are dedicated to provide a straightforward and effective strategy by integrating electrochemistry, nanotechnology, and membrane separation for the removal of arsenic and other similar heavy metals from water bodies.

A ClO-mediated photoelectrochemical filtration system for highly-efficient and complete ammonia conversion

The ability to convert excess ammonia in water into harmless N₂ is highly desirable for environmental remediation. We present a chlorine-oxygen radical (ClO)-mediated photoelectrochemical filtration system for highly efficient and complete ammonia removal from water. The customized photochemical device comprised a Ag-functionalized TiO₂nanotube array mesh photoanode and a Pd-Cu co-modified nickel foam (Pd-Cu/NF) cathode. Under illumination, holes generated at the anode catalyzed the conversion of H₂O and Cl^- to HOand Cl, respectively. In turn, these radicals then reacted further, yielding ClO, which selectively decomposed ammonia. The cathode enabled further reduction of anodic byproducts such as NO₃^- to N₂. The complete oxidation of all dissolved ammonia was achieved within 15 min reaction under neutral conditions, where N₂ was the dominant product. The impact of key parameters was assessed, which enabled the discovery of optimal reaction conditions and the proposal of the underlying working mechanism. The flow-through configuration demonstrated a 5-fold increase of ammonia oxidation rate compared to the conventional batch reactor. The role of ClO in the oxidation of ammonia was verified with electron paramagnetic resonance and scavenger studies. This study provided greater mechanistic insights into photoelectrochemical filtration technology and demonstrated the potential of future nanotechnology for removing ammonia.

Mitigation of Membrane Fouling Using an Electroactive Polyether Sulfone Membrane

Membrane fouling is the bottleneck limiting the wide application of membrane processes. Herein, we adopted an electroactive polyether sulfone (PES) membrane capable of mitigating fouling by various negatively charged foulants. To evaluate anti-fouling performance and the underlying mechanism of this electroactive PES membrane, three types of model foulants were selected rationally (e.g., bovine serum albumin (BSA) and sodium alginate (SA) as non-migratory foulants, yeast as a proliferative foulant and emulsified oil as a spreadable foulant). Water flux and total organic carbon (TOC) removal efficiency in the filtering process of various foulants were tested under an electric field. Results suggest that under electrochemical assistance, the electroactive PES membrane has an enhanced anti-fouling efficacy. Furthermore, a low electrical field was also effective in mitigating the membrane fouling caused by a mixture of various foulants (containing BSA, SA, yeast and emulsified oil). This result can be attributed to the presence of electrostatic repulsion, which keeps foulants away from the membrane surface. Thereby it hinders the formation of a cake layer and mitigates membrane pore blocking. This work implies that an electrochemical control might provide a promising way to mitigate membrane fouling.