High Desalination Research Articles

Porous N, P co-doping Ti3C2Tx MXene for high-performance capacitive deionization

The emerging energy-saving and environmentally friendly capacitive deionization (CDI) technology has attracted more and more attention. However, it remains a great challenge to develop CDI electrode materials with excellent comprehensive properties. Herein, the porous N, P co-doping Ti3C2Tx MXene (N, P-Ti3C2Tx) was prepared successfully by combining simple flocculation with an annealing process. Benefitting from the synergistic effect of the combination of porous structure and co-doping of N and P heteroatoms, the N, P-Ti3C2Tx exhibits substantial specific surface area, which provides more surface bounding active sites for electrochemical reactions, thus assisting to boost the CDI performance. As a result, the N, P-Ti3C2Tx exhibited an admirable salt (Na+) adsorption capacity of 53.3 mg g−1 and exceptional recycling property. Impressively, the N, P-Ti3C2Tx also exhibited superior desalination performance of Pb2+, characterized by an exceptionally high desalination capacity of up to 168.2 mg g−1 at 1.2 V, and the corresponding desalination rate reached 0.047 mg g−1 s−1. Additionally, the deionization mechanism involved was elucidated through a series of characterizations. This work will furnish an effective avenue for the innovative design of MXene-based electrode materials toward high-performance CDI.

Mussel-inspired co-deposition of catechol-amine and graphene oxide (GO) modified anion exchange membranes (AEMs) for antifouling

Mussel-inspired co-deposition has many applications in surface modification of polymer membranes. Organic fouling of ion exchange membranes is one of the common issues that hinder electrodialysis treatment of industrial wastewater. In this work, anion exchange membranes were surface-modified by the mussel-inspired co-deposition of catechol-amine and graphene oxide (GO) nanosheets. Results showed that co-deposition with catechol (CA) and m-phenylenediamine (MPD) as reactant monomers rapidly generated modifying layer on the AEM surface. And the addition of GO into co-deposition helped improve the homogeneity and reduce polymer particle aggregation. The synergistic effect of catechol-amine and GO nanosheets was beneficial to form uniform modifying layer with improved hydrophilicity and negative charge density of membrane surface. In eletrodialysis experiments with sodium dodecyl benzene sulfonate (SDBS) as model foulants, GO-CA-MPD-3h modified AEM maintained high desalination rate close to that without folants, indicating good modifying antifouling performance. Mussel-inspired co-deposition of catecholamines and functional materials give new insights into membrane modificatin through a feasible and cost-effective method

Simultaneous desalination and removal of organic pollutants in a novel bifunctional FCDI system: The enhancement by in-situ reutilization of chloride ions

A new system of flow electrode capacitive deionization coupled with in situ electro-oxidation (FCDI-EO) was constructed to achieve the degradation of organic pollutants while maintaining high desalination efficiency. The effects of different parameters of potential difference, electrolyte, and pH on the chloride removal performance of FCDI-EO and the removal performance of rhodamine B (RhB) were investigated. Under the optimal conditions of potential difference = 4 V, [Cl−] = 500 mg/L, and pH = 4, the removal of chloride ions, RhB and total organic carbon (TOC) was as high as 88.74 %, 99.02 %, and 87.82 %, respectively. The quenching experiments showed that hydroxyl radicals (OH) and reactive chlorine species (RCS) were involved in the FCDI-EO system. The liquid chromatography-mass spectrometry (LC-MS) analysis suggested the possible mineralization pathway of RhB. Furthermore, toxicity assessment analysis showed that the toxicity of the degradation intermediates of RhB decreased during the treatment. Overall, this study provides a promising process that reducing the generation of high-concentration saline water in desalination and in situ utilizing the Cl− gathered from the feed water. The findings of this study could provide useful guidance for the development of flow electrode capacitive deionization technology and organic pollutant control.

Carbon-modified bentonite ion-exchange electrode in rocking-chair capacitive deionization with superior desalination capacity and high stability

Conventional carbon electrodes possess low desalination capacity and poor cycling stability, while faraday electrode materials are not economical with limited resource for capacitive deionization (CDI) technology. Therefore, exploring new type of electrode materials with high desalination capacity, low cost and excellent cycle stability is highly desirable. Bentonite (Bent) is an excellent ion-exchange material, with high natural abundance, super stability, but it has low conductivity. In this paper, a nitrogen-doped carbon modified Bent (NC@Bent) was prepared by in-situ polymerization of dopamine on the surface of Bent followed by carbonization. The N,C-modified thin layer on Bent improved the conductivity, boosting the charge transportation and ion diffusion. The NC@Bent was used as ion-adsorption electrode, exhibiting excellent electro-adsorption behavior. In a rocking-chair CDI (RCDI) cell, it delivered an extraordinary desalination capacity of 82 mg g−1 and super cycling stability with 90 % capacity retention in 50 cycles. Finally, the total dissolved salts in the actual groundwater were effectively reduced by using the current RCDI cell, meeting the WHO recommendation for drinking water. In consideration of the unique feature of low-cost and non-toxicity of Bent, this ion-exchange electrode material (NC@Bent) has much potential for drinking-water purification.

Marrying Fe nanoclusters with 3D carbon nanofiber aerogels: Triggering fast and robust faradic capacitive deionization

Faradic-capacitive deionization (FDI) has emerged promising research branch of capacitive deionization (CDI) to address the crisis in freshwater supply due to its high desalination capacity and unique ion storage mechanism over traditional CDI. However, the ion-storage mechanism of FDI imposes notable limitations on its desalination kinetics, while issues such as volumetric expansion (as well as the damage caused to the composite material’s structure) contribute to poor cycling stability. Herein, we developed a rational material design of Fe nanocluster-impregnated CNFAs (Fe NCs@CNFAs) and further used it as chloride-capturing electrode for FDI. This unique nanostructure not only provides fast surface-driven pseudo capacitance but also establishes a flexible scaffold that effectively protects the Fe NCs from severe morphology changes. As a result, our Fe NCs@CNFAs-based FDI exhibited both ultrahigh desalination capacity (120.38 mg g−1) and fast desalination rate (0.42 mg g−1 s−1), with robust cycling stability (showing only a 15.25 % decrease in desalination capacity after 100 cycles). This study underscores the significance of the problem-driven approach by leveraging soft scaffold-protected ultrasmall nanocluster to induce fast and durable desalination performance.

Reactive P and S co-doped porous hollow nanotube arrays for high performance chloride ion storage

Developing stable, high-performance chloride-ion storage electrodes is essential for energy storage and water purification application. Herein, a P, S co-doped porous hollow nanotube array, with a free ion diffusion pathway and highly active adsorption sites, on carbon felt electrodes (CoNiPS@CF) is reported. Due to the porous hollow nanotube structure and synergistic effect of P, S co-doped, the CoNiPS@CF based capacitive deionization (CDI) system exhibits high desalination capacity (76.1 mgCl– g–1), fast desalination rate (6.33 mgCl– g–1 min–1) and good cycling stability (capacity retention rate of > 90%), which compares favorably to the state-of-the-art electrodes. The porous hollow nanotube structure enables fast ion diffusion kinetics due to the swift ion transport inside the electrode and the presence of a large number of reactive sites. The introduction of S element also reduces the passivation layer on the surface of CoNiP and lowers the adsorption energy for Cl– capture, thereby improving the electrode conductivity and surface electrochemical activity, and further accelerating the adsorption kinetics. Our results offer a powerful strategy to improve the reactivity and stability of transition metal phosphides for chloride capture, and to improve the efficiency of electrochemical dechlorination technologies.

Capacitive deionization technology with multi-stage treatment as an efficient desalination process for agricultural irrigation

Novel capacitive deionization (CDI) technology is recognized as a cheap desalination method and holds a promise to be deployed in low-profit fields such as agricultural and municipal works. In this study, the application feasibility of CDI technology in agricultural irrigation is thoroughly investigated. The desalination performance of three operation methods (“low flow rate”, “high applied voltage”, and “two-stage treatment”) are compared for treating artificial brackish water of 2000 mg L−1 to a set desalination target (600 mg L−1). Among these three methods, “two-stage treatment” overwhelms the other two methods regarding several desalination indicators, achieving a decent productivity (1.5 L h−1 m−2) with a small energy input of 1.4 kWh m−3. The modified Donnan model indicates that energy dissipation is mitigated in a high flow rate adopted in two-stage treatment, and meantime a high desalination capacity and a good charge efficiency are achieved. In addition, desalinated water with a salt concentration gradient is produced by the CDI module for tomato seedlings irrigation. Compared with the tomato seedlings irrigated by feedwater (2000 mg L−1), the total length and the biomass weight of those irrigated by desalinated water of 300 mg L−1 increase 51.1 % and 119.8 %, respectively. The research accomplishes a proof-of-concept of the agricultural application of CDI technology, and provides reliable data as the foundation for its future practical operation.

Plasma-assisted preparation of NiCoAl-layered double hydroxides with alarge interlayer spacing on carbon cloth forelectrochemical deionization

Capacitive deionization has been considered an emerging desalination technique in recent years, especially for its economic and energy-saving characteristics for brackish water. However, there are currently few studies on chloride ion removal electrodes, and the slow desalination kinetics limits their development. Ar-NiCoAl- layered double hydroxide (LDH)@ACC materials with an increased interlayer spacing were prepared by the in-situ growth of NiCoAl-LDHs nanosheet arrays on acid-treated carbon cloth (ACC) and subsequent Ar plasma treatment. The carbon cloth suppresses the agglomeration of the NiCoAl-LDHs nanosheets and improves the electrical conductivity, while the plasma treatment increases the interlayer spacing of NiCoAl-LDHs and improves its hydrophilicity. This provides rapid diffusion channels and more interlayer active sites for chloride ions, achieving high desalination kinetics. A hybrid capacitive deionization (HCDI) cell was assembled using Ar-NiCoAl-LDHs@ACC as the chloride ion removal electrode and activated carbon as the sodium ion removal electrode. This HCDI cell achieved a high desalination capacity of 93.26 mg g−1 at 1.2 V in a 1000 mg L−1 NaCl solution, a remarkable desalination rate of 0.27 mg g−1 s−1, and a good charge efficiency of 0.97. The capacity retention remained above 85% after 100 cycles in a 300 mg L−1 NaCl solution at 0.8 V. The work provides new ideas for the controlled preparation of two-dimensional metal hydroxide materials with a large interlayer spacing and the design of high-performance electrochemical chlorine ion removal electrodes.

Entropy Engineering Constrain Phase Transitions Enable Ultralong-life Prussian Blue Analogs Cathodes.

Prussian blue analogs (PBAs) are considered as one of the most potential electrode materials in capacitive deionization (CDI) due to their unique 3D framework structure. However, their practical applications suffer from low desalination capacity and poor cyclic stability. Here, an entropy engineering strategy is proposed that incorporates high-entropy (HE) concept into PBAs to address the unfavorable multistage phase transitions during CDI desalination. By introducing five or more metals, which share N coordination site, high-entropy hexacyanoferrate (HE-HCF) is constructed, thereby increasing the configurational entropy of the system to above 1.5R and placing it into the high-entropy category. As a result, the developed HE-HCF demonstrates remarkable cycling performance, with a capacity retention rate of over 97% after undergoing 350 ultralong-life cycles of adsorption/desorption. Additionally, it exhibits a high desalination capacity of 77.24mg g-1 at 1.2V. Structural characterization and theoretical calculation reveal that high configurational entropy not only helps to restrain phase transition and strengthen structural stability, but also optimizes Na+ ions diffusion path and energy barrier, accelerates reaction kinetics and thus improves performance. This research introduces a new approach for designing electrodes with high performance, low cost, and long-lasting durability for capacitive deionization applications.

Designing NiFe-metal organic frameworks@NiFe-layered double hydroxide/carbon fiber self-supporting electrode for enhanced capacitive deionization

Self-supporting electrode benefits to enhance the desalination capacity and maximize the capacitance retention by avoiding the usage of organic binders and conductive additives in capacitive deionization (CDI). In this work, we design a self-supporting electrode of NiFe-metal organic framework@NiFe-layered double hydroxides/carbon fiber (MOF@LDH/CC) for highly efficient CDI. The cross-linked CC provides a unique network structure to promote the diffusion of salty ions, leading to high desalination kinetics. On the other hand, the NiFe-MOF acts as seed to induce the growth of NiFe-LDH which not only block the agglomeration of NiFe-LDH layers, but also strengthen the linkage between the CC and NiFe-LDH. As expected, the optimized MOF@LDH/CC//activated carbon CDI system achieves high initial salt removal capacity of 0.033 mg/cm2 in 1000 μS/cm NaCl solution, which decreases to 0.026 mg/cm2 after 30 cycles. The capacity decline is ascribed to the salt deposition during the cycling, which can be observed from the structural evolution. Further, the X-ray photoelectron spectra verifies the reversible chloride ions electro-adsorption/desorption by MOF@LDH/CC. Meanwhile, the porous fibrous structure of MOF@LDH/CC electrode is remaining after few cycles, highlighting the robust structure.

Work-function-prompted interfacial charge kinetics in hierarchical heterojunction flexible electrode for efficient capacitive deionization

The growing challenge of water scarcity has spurred extensive research into the development of advanced freestanding pseudocapacitive electrode materials. These electrodes, characterized by their controlled morphology, mechanical complexity, and enhanced desalination capabilities, are advancing water treatment technologies. Additionally, electrodes with interfacially influenced heterostructures demonstrate substantial potential to enhance electrochemical kinetics. However, their widespread adoption is hindered by intricate synthesis procedures and the necessity for multiple discrete components. Herein, the report introduces a cohesive approach that utilizes electrospinning and carbonization to create a freestanding, hierarchically porous nitrogen-doped carbon nanofiber network encapsulating FeNi3 alloy (FeNi3@CNFs) for desalination applications. The method enhances the interfacial effect, mitigates volume changes during sodium ion adsorption and desorption, and improves interfacial stability. By capitalizing on structural and compositional advantages, the novel FeNi3@CNFs electrode delivers outstanding electrochemical properties, including a high desalination capacity (46.47 mg g−1 at 1.2 V), rapid desalination rate (0.77 mg g−1 min−1), and enhanced cyclic durability. Computational analysis via Density Functional Theory shows that the work function prompts a surface charge redistribution at the FeNi3@CNFs heterojunction, optimizing the surface electronic structure and reducing the energy barrier for adsorption. The modification significantly boosts the diffusion kinetics of sodium adsorption. The study delineates a comprehensive methodology for fabricating high-performance heterostructured electrode materials that are effective for capacitive deionization.

High capacity rocking-chair capacitive deionization using highly crystalline sodium cobalt hexacyanoferrate (NaCoHCF) electrodes

Prussian blue analogue (PBA) electrodes are widely used cation-selective electrodes for electrochemical desalination technologies due to their high specific capacity rates and fast kinetic properties. Despite the fact that previous studies of PBAs for electrochemical desalination have shown remarkable desalination capacity levels, they remain insufficient if used to desalt highly concentrated salt water such as seawater. Here, we applied highly crystalline sodium cobalt hexacyanoferrate (NaCoHCF) electrodes, a type of PBA that can utilize two redox active sites, to a rocking-chair capacitive deionization (RCDI) process. The specific capacity of the NaCoHCF electrode using two redox active sites was 88 mAh g-1 (active material: 110 mAh g-1), confirmed to be 1.5 times higher than that of PBA electrode that use one redox active site. As a result of desalination tests, this system achieved a high desalination capacity of 123 mg g-1 (active material: 154 mg g-1) with 88% ion removal in a 500 mM NaCl solution. The results of this study present a considerable increase in the desalination capacity through the introduction of NaCoHCF electrodes that utilize two redox active sites in the RCDI system.

Tailoring hierarchical structures in cellulose carbon aerogels from sugarcane bagasse using different crosslinking agents for enhancing electrochemical desalination capability

Sugarcane bagasse is one of the most common Vietnamese agricultural waste, which possesses a large percentage of cellulose, making it an abundant and environmentally friendly source for the fabrication of cellulose carbon aerogel. Herein, waste sugarcane bagasse was used to synthesize cellulose aerogel using different crosslinking agents such as urea, polyvinyl alcohol (PVA) and sodium alginate (SA). The 3D porous network of cellulose aerogels was constructed by intermolecular hydrogen bonding, which was confirmed by Fourier transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and nitrogen adsorption/desorption. Among the three cellulose aerogel samples, cellulose – SA aerogel (SB-CA-SA) has low density of 0.04 g m−3 and high porosity of 97.38%, leading to high surface area of 497.9 m2 g−1 with 55.67% micropores of activated carbon aerogel (SB-ACCA-SA). The salt adsorption capacity was high (17.87 mg g−1), which can be further enhanced to 31.40 mg g−1 with the addition of CNT. Moreover, the desalination process using the SB-ACCA-SA-CNT electrode was stable even after 50 cycles. The results show the great combination of cellulose from waste sugarcane bagasse with sodium alginate and carbon nanotubes in the fabrication of carbon materials as the CDI-utilized electrodes with high desalination capability and good durability.

A hybrid electrochemical system for spontaneous green‑hydrogen production with simultaneous desalination using catechol oxidation

Green hydrogen, commonly produced through water electrolysis, has attracted considerable attention owing to its energy-efficient and eco-friendly properties. However, since conventional water electrolysis system has fatal drawbacks owing to the high process cost and energy requirements, various approaches are being adopted to increase its energy efficiency. In this study, a novel hybrid system for green hydrogen production was designed by replacing the oxygen evolution reaction (OER) with electrochemical oxidation of catechol (CAT). CAT is an environmental pollutant generated by diverse industries and needs to be further treated because of its toxicity to humans and nature. Accordingly, to facilitate the degradation of CAT and increase the energy efficiency, the pH values of the anolyte (containing CAT) and catholyte were adjusted to alkali and acid, respectively. Two types of ion-exchange membranes (IEMs; anion-/cation-exchange membranes) were coupled to divide the hybrid cell into three compartments, and a buffer solution (NaCl solution) was injected between the IEMs. As a result, the hybrid system output 3.75 mW/cm2 of electricity, spontaneously produced hydrogen with 4.2 mL/h of hydrogen production rate and removed ions from the buffer solution with 0.46 mg/cm2∙min of high desalination rate.

Rational design of Core-Shell heterostructured CoFe@NiFe Prussian blue analogues for efficient capacitive deionization

Rational design of stable and high-capacity faradaic electrode materials is crucial for enhancing the desalination performance of hybrid capacitive deionization (HCDI). In this work, to fully exploit the advantages of high-capacity CoFe Prussian blue analogs (PBA) and structurally stable NiFe PBA, a core–shell heterostructured CoFe@NiFe PBA is successfully synthesized by a two-step co-precipitation method. The construction of the core–shell heterostructure not only suppresses dissolution of the CoFe PBA core, but also facilitates fast charge transfer and efficient ion diffusion during Na+ ions insertion/extraction. With an optimal NiFe PBA shell thickness of 30 nm, the core–shell structured PBA electrode demonstrates outstanding cycling performance with a capacity retention of 72.6 % over 10,000 charge/discharge cycles. Moreover, when utilized as the cathode material in HCDI, the core–shell heterostructured PBA exhibits intriguing desalination performance, including a high desalination capacity of 49 mg g−1 and excellent desalination stability over 200 cycles (77.7 %). This paper presents a straightforward strategy for designing core–shell heterostructured PBA electrode, with the potential to advance the development of high-performance capacitive desalination.

Development of a unique integrated bioreactor for simultaneous desalination and bioenergy and biohydrogen production

In the wastewater treatment challenge, it is really essential to develop integrated systems in reducing greenhouse gases, producing green energy and achieving sustainable development. In this regard, an integrated electro-biomembrane reactor was developed and performed in this study for simultaneous biohydrogen (bioH2) production from energetic poplar leaves using dark fermentation (DF) process, conventional H2 production, bioenergy production in the DF process, and saline water desalination in a single system. The results of this study showed that pH was the main controlling parameter in bioH2 production, and the superior production of 40.2 mL/g-biomass was obtained at a pH of 5.5. The maximum current and power density values were 2861.7 mW/m2 and 2819.4 mA/m2 at pH 5.5 under improved conditions. Furthermore, the maximum conventional H2 production was found to be 1341.6 mL using 2 M of KOH solution. Overall, the results further proved that the proposed integrated system can be a sustainable and promising process for industrial applications, considering its high desalination, energy production, and conventional and biological H2 production efficiencies.

Application of a functionalized thin-film composite nanofiltration membrane in water desalination

To prepare a thin-film nanocomposite (TFN) nanofiltration (NF) membrane, characterized with high desalination rate and antifouling performance, carboxylated multi-walled magnetic 1,2,3,4-butanetetracarboxylic acid carbon nanotubes (hereafter, the C-MWCNT-MBTCA) with a choice of hydrophilic groups were initially synthesized in this study, and then incorporated into the polyamide (PA) layer via interfacial polymerization (IP). After that, the surface morphology and hydrophilicity of the fabricated NF membrane was examined by the field emission scanning electron microscopy (FESEM) and water contact angle measurements, respectively. To assess the membrane application, the solutions (2000 mg/L) of sodium sulfate (Na2SO4), magnesium sulfate (MgSO4), calcium chloride (CaCl2), and sodium chloride (NaCl) were consistently tested. On account of the ample carboxylic acid (R-COOH) groups in the modified TFN membrane, the study outcomes revealed that the given membrane could enhance the flux along with the desalination rate upon the addition of the C-MWCNT-MBTCA (0.04 wt%). Likewise, the pure water flux significantly grew from 58.8 to 110.5 Lm-2h−1 after the utilization of the C-MWCNT-MBTCA (0.04 wt%), and the Na2SO4 removal rate promoted from 87 to 98 %. Ultimately, it was established that the C-MWCNT-MBTCA could be used as an economical modifying agent to boost the performance of NF membranes for water desalination purposes.

Bismuth Nanoparticles Encapsulated in a Porous Carbon Skeleton as Stable Chloride-Storage Electrodes for Seawater Desalination

Cost-effective bismuth (Bi) boasts a high theoretical capacity and exceptional selectivity towards Cl- ion storage, making it a promising material for desalination batteries (DBs). However, the substantial volume expansion and low conductivity severely hinder the cycling performance of Bi-based DBs. In this study, a carbon-layer-coated Bi nanocomposite (Bi@C) was synthesized by pyrolyzing a metal–organic framework (Bi-MOF) containing Bi using a straightforward method. The results show that the Bi@C synthesized under the condition of annealing at 700 °C for 2 h has the optimum properties. The Bi@C has good multiplication performance, and the desalination capacity is 106.1 mg/g at a high current density of 1000 mA/g. And the material exhibited a high desalination capacity of 141.9 mg/g at a current density of 500 mA/g and retained 66.9% of its capacity after 200 cycles. In addition, the Bi@C can operate at a wide range of NaCl concentrations from 0.05 to 2 mol/L. The desalination mechanism analysis of the Bi@C revealed that the carbon coating provides space for Bi particles to expand in volume, thereby mitigating the issues of electrode material powdering and shedding. Meanwhile, the porous carbon skeleton establishes electron and ion channels to enhance the electrode material’s conductivity. This research offers a promising strategy for the application of chloride-storage electrode materials in electrochemical desalination systems.

Integrating FeOOH with bacterial cellulose-derived 3D carbon nanofiber aerogels for fast and stable capacitive deionization based on accelerating chloride insertion

Faradic capacitive deionization (FDI), as an emerging research branch of capacitive deionization (CDI), has shown its great potential to relieve global water stress owing to its high desalination capacity/efficiency, flexible scale, and zero secondary pollution characteristics. However, the slow desalination kinetics and poor cyclic stability of the anion-capturing electrode of current FDI systems greatly limit its practical application. Herein, we proposed a strategy of interweaving FeOOH nanospindle inside the 3D network structure of carbon nanofiber aerogel to construct a 3D network structure (CNFAs@FeOOH) and further used it as a chloride capture electrode for FDI. As a result, the FDI system equipped with CNFAs@FeOOH enjoys excellent desalination performance with an ultrahigh desalination rate of up to 0.33 mg g−1 s−1. More importantly, the CNFAs@FeOOH-based FDI system enjoys excellent cycling stability with no significant decrease in 100 cycles and only 17.85 % decrease in 200 cycles.

Facial synthesis of FeOOH array-anchored carbon fiber as flow-through chloride-capturing electrode for ultrafast and super-stable capacitive deionization

Faradic-based capacitive deionization (FDI) has been recognized as one of the most promising technologies to solve the freshwater crisis, yet was plagued by two most serious issues, i.e., slow desalination kinetics and poor cyclic stability. Herein, an ultrafast and super-stable FDI system is successfully developed based on the employment of a pseudocapacitive material as flow-through chloride-capturing electrode. While the pseudocapacitive material, anchoring FeOOH arrays on the surface of commercial carbon fiber cloth (CF@FeOOH) ensures high desalination durability by preventing possible FeOOH aggregation through the carbon fiber framework, the unique flow-through electrode enables fast mass transfer by channeling the feed stream inside its microchannels. Consequently, the FDI system equipped with flow-through CF@FeOOH electrodes displays an excellent desalination rate of 0.48 mg g−1 s−1 with ultra-robust cyclic stability (no reduction after 60 cycles and only 14.9 % capacity reduction after 150 cycles), while maintaining its high desalination capacity of 52.04 mg g−1, exemplifying the critical importance of both delicate material design and rational cell architecture.