Abstract More effective, environmentally friendly, and widely used desalination technologies have been developed as a result of the worldwide freshwater shortage situation. Small seawater distillation dispenser with vacuum chamber, which reduces seawater’s boiling point to allow for low-temperature evaporation, is one promising technique. In order to produce fresh water from seawater, this study intends to assess the performance characteristics of a vacuum-chambered MED (Multi-Effect Distillation) dispenser as a small desalination system. Lab-scale MED units with variable working parameters, such as vacuum pressures ranging from 20 kPa to 70 kPa, operating temperatures between 50 and 80 °C, and three chambers, were designed and tested as part of the research methodology. Fresh water production rate, gained output ratio (GOR), and salt rejection efficiency were among the performance metrics examined. Under working circumstances of 50 kPa, the experimental results demonstrate that a drop in vacuum pressure significantly enhances the freshwater production rate in comparison to atmospheric pressure. An optimal GOR value of 0.008 in a 3-effect configuration, the system’s energy efficiency is demonstrated. According to the study’s findings, vacuum-chambered MED dispensers hold enormous promise as portable, high-performing, eco-friendly desalination equipment. These results are anticipated to serve as the foundation for the creation of small, renewable energy-based desalination devices that can be used in isolated locations with inadequate clean water infrastructure and along coastlines.

Synergistic water activation on high-entropy alloy oxides enables ultralow-enthalpy solar desalination.

Pervaporation (PV) is a cost-efficient separation process successfully used in the dehydration of organic solutions, which is also regarded as a promising concentrating and desalination technology. However, the performance of water reclamation by PV from real high-strength wastewater is still lacking. In this study, the feasibility of reclaiming water from real leachate reverse osmosis concentrate was investigated with both laboratory and pilot-scale apparatus. With a feed temperature set to 70 ℃, the laboratory-scale setup achieved a water flux of 17.4 LMH, while the pilot-scale system obtained 8.9 LMH with flat membrane modules. Increasing the feed temperature from 70 to 85 ℃ resulted in a minimal enhancement of water flux, whereas a linear increase in water flux was observed as osmotic side pressure decreased. Results showed high salt rejection (> 99.8%) and COD removal efficiency (94.6%) under all operating conditions, and the reclaimed water could meet the quality requirements for reuse.

Achieving both efficient water transport and complete salt rejection in synthetic water channels continues to pose a significant challenge for reverse osmosis (RO) desalination. In this study, we design a series of functional porous organic cages (POCs) by grafting fluorine (-F), hydroxyl (-OH), amino (-NH2), and methyl (-CH3) into the interior of a prototypical CC3 cage to construct CC3-F, CC3-OH, CC3-NH2, and CC3-CH3 channels, respectively. Subsequently, molecular dynamics simulations are conducted to explore how different chemical functional groups influence the desalination performance of these CC3-based channels embedded in a lipid bilayer. It is revealed that water transports through the channels in a single-file manner, and all the channels exhibit complete salt rejection. Water fluxes follow the order: CC3-F > CC3-OH > CC3 > CC3-NH2 > CC3-CH3, as attributed to the steric hindrance and hydrogen bonding of functional groups that affect water-channel interaction and alter the dynamic configuration of confined water molecules in the channels. Furthermore, wetting-dewetting transition is found to be largely suppressed in the hydrophilic channels. From temperature-dependent water flux, activation energies are estimated to range from 12 to 20 kJ/mol in CC3-based channels, lower than those in polyamide RO membranes. From bottom-up, this simulation study reveals molecular-level mechanisms of the role of functionalization in tuning water transport in one-dimensional subnanometer channels and provides a theoretical basis for designing high-performance synthetic water channels toward next-generation desalination technologies.

This research focuses on synthesizing a novel antiscalant and exploring the inhibition of CaSO4 and CaCO3 scaling in reverse osmosis desalination technology. The antiscalant bearing residues of aspartic and maleic acid (MA) has been synthesized via alternate cyclopolymerization of N,N-diallylaspartic acid [(H2CCH-CH2)2NH+CH-(CO2 -)-CH2CO2H] and MA. The performance of the antiscalant and several commercial ones was evaluated against supersaturated CaSO4 and CaCO3 solutions. At a 2.5 ppm concentration, the antiscalant imparted percent scale inhibition (PSI) of ≈100% for CaSO4 until 820 min [i.e., induction time (IT) after which scaling starts]. The superior performance of the antiscalant was ascertained at 0.5 and 1 ppm concentrations at 40 °C, where it showed ITs of 40 and 60 min, respectively, which are sufficient to mitigate scaling during the 15 min residence time of the reject brine in the osmosis chamber. The antiscalant was also examined for the mitigation of CaCO3 scaling.

Photothermal membranes driven by solar energy represent a promising approach for sustainable and cost-effective desalination and wastewater treatment. Solar energy's renewability and low environmental impact drive its adoption in desalination technologies. In this work, chemical vapor deposition polymerization (CVDP) is used to deposit high-performance polypyrrole (PPy) coatings on two different fabric types: woven and nonwoven, enabling broad-spectrum solar light absorption and efficient thermal conversion for enhanced water evaporation. This study investigated the efficacy of different oxidizing agents in initiating the CVDP process and in depositing PPy layer on the substrate surface, for use as a photothermal membrane to harvest freshwater and salt from different saline wastewater samples. The goal is to achieve efficient polymerization, targeting pyrrole usage as low as 15 μL for perfect PPy deposition. Among the investigated oxidizing agents, copper chloride and ammonium persulfate yielded the most effective performance in producing PPy-coated photothermal membranes. These membranes demonstrated superior light absorption and achieved surface temperatures of 63°C and 60°C under simulated 1 sun illumination (1 kW m- 2), showing facilitated enhanced water evaporation rates of 0.95 and 0.93 kg m- 2 h- 1, respectively. Meanwhile, a a water evaporation rate of 2.91 kg m- 2 h- 1 under 3 sun illumination was obtained. Furthermore, the developed robust photothermal membranes tested against different saline solutions, including NaCl, CuSO4.5H2O, and FeCl3 for simultaneous water evaporation and salt harvesting under solar simulator. A developed A4-size photothermal membrane from non-woven fabric was tested using actual brine water sample under natural sunlight for one week. The used photothermal membranes showed the recyclability and durability during the tests.

Solar interfacial evaporation has gained considerable attention as a sustainable and eco-friendly desalination technology. However, challenges including limited water transport, salt crystallization, biofouling, and insufficient long-term stability remain critical. In this work, a radiate-layered graphene nanoplatelets/poly(vinyl alcohol-co-ethylene) (GN/EVOH) nanofiber aerogel was fabricated through graphene nanosheet-induced assembly and radial ice-templating. This hierarchical structure promotes synergistic vertical and radial transport of water and salt ions, effectively suppressing salt accumulation. The incorporation of graphene also imparts strong antibacterial properties to the evaporator. Under 1 sun illumination (1 kW m-2), the aerogel achieved a high evaporation rate of 2.14 kg m-2 h-1 with an energy conversion efficiency of 98%. It maintained stable performance over multiple cycles in 20 wt % brine without salt crystallization, demonstrating excellent salt resistance. Moreover, the evaporator exhibited effective purification of simulated seawater, dye wastewater, acidic/alkaline solutions, and oil-water emulsions. These results indicate that the designed evaporator holds strong potential for practical applications in seawater desalination and wastewater treatment.

The global shortage of freshwater, intensified by rising salinity in natural water sources, calls for scalable and energy-efficient desalination technologies. Interfacial solar-driven evaporation offers a promising solution, yet its practical implementation is hindered by high-cost photothermal materials and complex fabrication. Herein, we develop a flexible, self-floating electrospun bilayer membrane composed of Ce-doped Cu-based MOFs, multiwalled carbon nanotubes, polyvinylidene fluoride, and polyacrylonitrile, which was designed for efficient photothermal seawater desalination. A key distinguishing feature lies in the Ce doping strategy. During calcination, Cu-MOFs yield CuO and undesired Cu2O, which reduce photothermal efficiency. The introduced cerium species form CeO2/Ce2O3 can catalytically oxidize residual Cu2O into CuO to enhance light absorption. X-ray photoelectron spectroscopy confirms the formation of CeO2/CuO heterojunctions with improved interfacial synergy. Under 1 kW·m-2 solar irradiation, the optimized membrane reaches a surface temperature of 61.4 °C and delivers a high evaporation rate of 1.98 kg·m-2·h-1. The membrane exhibits strong mechanical strength, reaching a tensile value of 9.92 MPa. It also demonstrates a rapid thermal response by cooling from 61.4 to 26.1 °C within 90 min, which highlights its focus on efficient evaporation dynamics rather than heat retention. This work offers a cost-effective and scalable strategy for interfacial solar-driven evaporation membrane fabrication and introduces a Ce-assisted catalytic route to enhance photothermal conversion via compositional control and interfacial engineering.

Graphene oxide (GO) membranes have emerged as promising candidates for water desalination as a result of their structural and transport properties. In this study, we employ fully atomistic classical molecular dynamics simulations to investigate the performance of monolayer GO membranes featuring pore- and slit-like nanostructures. We analyze the influence of the width of the slits, ranging from 0.8 to 1.5nm, on water transport and salt rejection by monitoring the spatial and temporal distributions of water molecules and ions. Furthermore, we assess the effect of applied pressure on water density profiles and compute the potential of mean force for water molecules traversing the slits. Our results reveal that slits offer tunable transport characteristics and that nanopores generally outperform slits in the combined metrics of water flux and ion exclusion at low pressures. At higher pressures, however, 1.0-1.5nm slits exhibit a permeability gain that can exceed comparable nanopore systems, with a reduction in salt rejection, whereas 0.8nm slits retain near-complete ion exclusion over the range examined. These findings delineate operating regimes in which each architecture is advantageous and guide the optimization of nanostructure design for advanced desalination technologies.

Solar steam generation is widely recognized as a sustainable and cost-effective technology for seawater desalination and wastewater purification, offering an efficient solution to mitigate global water scarcity. Herein, a populus-inspired aerogel evaporator composed of hydrophilic poly(vinyl alcohol) (PVA) and carbonized straw was fabricated through a directional freezing strategy. The incorporation of carbonized straw significantly enhanced the solar absorption of the evaporator to 95.1% while effectively reducing the material cost. Notably, the custom-designed vertically aligned channels in the evaporator significantly reduce water transport resistance, thereby enabling more rapid and efficient water delivery. Benefiting from its precisely tailored structure, the aerogel evaporator achieves a water evaporation rate of up to 2.6 kg m-2 h-1 and a solar energy conversion efficiency as high as 98.2% under 1-sun illumination (1 kW m-2). Moreover, the evaporator exhibits excellent cycle stability and high practical applicability. This work presents a promising and practical strategy for fabricating highly efficient, eco-friendly, and cost-effective aerogel evaporators, demonstrating significant potential for real-world applications in seawater desalination and wastewater treatment.

The development of cellulose triacetate (CTA)-based reverse osmosis membranes offers a sustainable approach to alleviating the global freshwater crisis, yet overcoming the inherent permeability-selectivity trade-off remains a significant challenge. Herein, we propose a homologous matching strategy to address the trade-off by incorporating carbon dots (M-CDs) derived from m-phenylenediamine (MPD) into the interfacial polymerization process between CTA and polyamide (PA). Systematic characterization and molecular dynamics simulations reveal that M-CDs, which are structurally analogous to the MPD monomer, promote monomer diffusion, regulate cross-linking density, and refine the microstructure of the PA layer. At an optimal M-CDs concentration, the resulting membrane achieves simultaneous enhancements in both salt rejection (99.1% vs. 96.5%) and water flux (18.3 vs. 15.2 L·m-2·h-1), thus surpassing conventional CTA membranes. The incorporation of M-CDs results in a thinner, denser, and more hydrophilic barrier layer with reduced pore size and narrowed distribution, as confirmed by post-annealing structural analysis. Moreover, hydrogen bonding between M-CDs and MPD improves chlorine resistance, maintaining high performance even after exposure to 2000 ppm NaClO solution. Molecular dynamics further illustrate that M-CDs promote water cluster transport while hindering ion penetration, thereby effectively mitigating the trade-off. The innovative use of homologous carbon dots to optimize the CTA-PA interface through structural matching, offering inspiring avenues for developing advanced bio-derived desalination technologies.

Plasmonics-enabled advanced technologies for water purification, desalination, and environmental monitoring

Electrodialysis (ED) is a promising seawater desalination technology using electricity. However, the existing research studies on ED mainly focus on design of electrode materials and device structure. The ED is a multiscale and multi-physical process with multiple influencing parameters. Under these circumstances, the complicated ED process needs to be unified for understanding its physical essence and further optimization. In the current work, a similarity principle-based multiscale model is constructed to analyze ion migration mechanism inside ED device. The multiscale model is developed by correlating cation and anion concentration difference in a mesoscopic nanopore with macroscopic space charge density. On the basis of non-dimensionalization of Poisson-Nernst-Planck equations, the mesoscopic model of ED is unified with three dimensionless variables instead of eight-dimensional input parameters, which can be categorized as representative of ion absorption capability, ion transport characteristic, and nanopore characteristic. Then, the macroscopic model of ED is further unified using 6 dimensionless variables instead of 12-dimensional input parameters, and their physical meaning include ion absorption capability, ion transport characteristic, ion migration driving force, and desalination tank characteristic. The similarity principle of multiscale ED process is verified through nine dimensional different cases with identical dimensionless variables. The dimensionless cation-anion difference in nanopores of mesoscopic model varies within 0.25%, and the dimensionless outlet Na⁺ concentration of macroscopic model changes within 0.05%. Besides, a multi-physical sensitivity analysis is also carried out using the Taguchi method to clarify dominant parameters for ED. The Taguchi sensitivity analysis quantifies parameter contribution to seawater desalination rate in ED as seawater temperature 39.74%, initial ion concentration 15.94%, applied electric potential 15.91%, desalination tank length 11.45%, ion exchange membrane porosity 8.76%, and seawater flow velocity 8.19%. The current work lays a theoretical foundation for developing experimental correlations of ED, and it also contributes to rapid sampling generation in artificial intelligence prediction.

With increasing water scarcity, capacitive deionization (CDI) has emerged as a promising desalination technology due to its cost-effectiveness and environmental friendliness. However, electrode materials significantly influence the CDI performance. To address the poor cycling stability of manganese-based Prussian blue analogs (MnHCF), this study synthesized biomass-derived porous carbon (FSB850) from the bark of Firmiana simplex (commonly known as Chinese parasol tree, synonymous with Firmiana platanifolia) via KOH activation for use as an anode, paired with MnHCF as a cathode. Electrochemical and desalination tests revealed a synergistic effect between the two materials, achieving a high salt adsorption capacity (SAC) of 25.80 mg·g-1 in 500 mg·L-1 NaCl solution and 83.72% cycling stability over 100 cycles. The results demonstrate the potential of biomass-derived carbon for enhancing CDI performance and provide insights into sustainable electrode design. Moreover, we observed that the asymmetric device demonstrated superior SAC under a constant current of 0.053mA compared to that at a constant voltage of 1.4V, indicating a potential pathway toward achieving lower energy consumption in capacitive deionization operations.

ABSTRACT Advanced desalination technologies are crucial for addressing the growing global freshwater shortage crisis. Capacitive deionization (CDI) is a relatively new energy‐efficient desalination technology that has emerged in recent years. Advanced electrode materials are crucial for CDI. While research predominantly targets cathode materials for Na + capture, the equally critical challenge of chloride ion Cl − removal remains relatively underexplored, and electrode materials specifically designed for efficient chloride ion removal in CDI have received relatively little attention, limiting the progress of CDI‐based desalination technology. Here, we developed a viologen‐based cationic covalent organic frameworks (COFs)‐based active anode material exhibiting unique pseudocapacitive behavior and excellent chemical stability. Experiments demonstrate that an asymmetric electrode based on the TAPT‐BDB‐COF(Cl − )//MnO 2 (Na + ) system exhibits a low specific energy consumption of 80.70 kJ mol − 1 NaCl and maintains high capacitance retention after 500 cycles. A membrane capacitive deionization (MCDI) system assembled based on this material achieves a specific adsorption capacity of 87.2 mg g − 1 at 1.5 V and a low salt concentration of 500 mg L − 1 , increasing to 124.57 mg g − 1 at a high salt concentration of 3000 mg L − 1 . Performance remains stable after 20 desalination/regeneration cycles. This material serves as a valuable reference for the development of efficient electrode materials for capacitive deionization and chlorine removal technologies.

Freshwater scarcity has become a critical global issue, highlighting the urgent need for low-cost and efficient technologies for seawater desalination and wastewater purification. Inspired by the hopper-shaped corolla of the Morning Glory, which efficiently concentrates sunlight and directs water along its conical surface, we developed a paper-based solar evaporator constructed from cellulose paper via laser-induced graphene (LIG) and further modified with polydopamine (PDA) to enhance hydrophilicity. The paper substrate was folded into a three-dimensional (3D) conical structure, which enlarged the evaporation area, improved light absorption, and optimized thermal management. Under 1 sun irradiation, the optimized 3D device achieved an evaporation rate of 2.02 kg m-2 h-1 with an efficiency of 125.1%, outperforming its two-dimensional counterpart. The conical geometry also facilitated edge crystallization of salts, ensuring long-term operational stability. Outdoor tests further verified its capability for freshwater production, demonstrating the potential of this bioinspired, low-cost, and scalable paper-based evaporator for sustainable desalination and clean water generation.

Efficient solar-driven interfacial evaporation requires coordinated photon absorption, heat confinement, and directional water delivery, yet current directional evaporators rarely achieve materials-level anisotropy to regulate photon-phonon-water coupling. Here, we report a 3D-printed anisotropic channel architecture (a-BTCG) that co-engineers directional geometry with preferential alignment of Ti3O5 nanoparticles, boron nitride (BN) nanosheets, and chitosan to form an integrated transport framework. The a-BTCG delivers a high evaporation rate of 5.43 kg m-2 h-1 under 1 sun and maintains stable performance for over 200 h in 20 wt.% NaCl, enabled by fast water flux (1.13 × 10-2 µm3 s-1) and enhanced in-plane thermal conductivity (2.73 W m-1 K-1). Mechanistic investigations reveal that aligned BN establishes continuous phonon-guided thermal pathways for heat localization, while the Ti3O5-BN hybrids enhance broadband absorption via reduced reflectance and multireflection in oriented channels. Chitosan mediates interfacial water structuring, lowers effective evaporation enthalpy, and sustains salt-resistant replenishment. The combined structural and materials-level anisotropy, therefore, overcomes conventional trade-offs in light absorption, heat dissipation, and water supply. This work demonstrates the potential of 3D printing-assisted alignment engineering for high-performance solar evaporators and provides a generalizable platform for advanced desalination and environmental thermal-management technologies.

Recently, numerous nations have found themselves in urgent need of an effective water desalination method that utilizes less energy and addresses water scarcity. A low-pressure desalination system is an appropriate technology for many regions due to its benefits, including minimal energy usage to achieve the evaporation threshold, substantial water output, and high-quality pure water. This work primarily aims to ensure the sustainability of low-pressure solar-powered desalination technology combined with a finned natural air-cooling condenser by providing a comprehensive analysis of the exergy, economic, and environmental aspects. Furthermore, innovative technology is a pioneer in generating freshwater continuously without affecting system pressure. Ambient temperature serves as a crucial sign of climate conditions, influencing the level of freshwater productivity, particularly when utilizing a natural air-cooled condenser. Consequently, this temperature has been thoroughly investigated through experiments and exergy analysis. Under the optimal conditions for this study, hsw = 15 cm, Tsw = 80 °C, and Tamb = 28 °C, the maximum productivity and GOR were obtained as 1020 g/hr and 1.2, respectively. Exergetic efficiency can reach a maximum of 3.48%. The economic analysis of the proposed system indicates that the cost of freshwater productivity is USD 0.042 per kilogram. Furthermore, the device’s first cost recovery period is roughly 183 days or 3.6% of its lifetime. The quantity and price of diluted CO2 over the lifetime of the device are 13 tons of CO2/year and 188.5 USD/year, respectively.

Access to safe drinking water remains a critical challenge in coastal West African urban centers, particularly in resource-limited settings such as Fresco, Côte d'Ivoire. This study evaluates the potabilization potential of the Bolo and Niouniourou rivers to inform sustainable water supply strategies in hydrogeologically complex estuarine environments. Water samples were collected from 20 stations during the peak flood period (July 2025) and analyzed for 24 physico-chemical parameters. Results revealed contrasting hydrochemical patterns between the two rivers driven by differential hydrodynamic forcing. The Bolo River maintained a freshwater facies (mean conductivity: 1,141µS/cm; dissolved oxygen: 6.28mg/L) under fluvial dominance, where high flood discharge effectively repelled saltwater intrusion through hydraulic flushing mechanisms. Conversely, the Niouniourou River exhibited severe mineralization (conductivity: 3,308µS/cm; chlorides: 912mg/L), attributable to tidal inertia and saltwater trapping that persists despite elevated discharge during the monsoon season. Compliance assessment against WHO drinking water guidelines confirmed the Bolo River's suitability for conventional treatment pathways, whereas the Niouniourou River's chronic salinity burden renders it unsuitable for potabilization without prohibitively expensive desalination technologies. These findings underscore the fundamental importance of hydrodynamic forcing in governing coastal water resource quality and accessibility. The study demonstrates that site-specific hydrodynamic assessment is essential for evidence-based water supply planning in estuarine contexts.

Capacitive deionization (CDI) is an emerging technology for seawater desalination. Puckered p-block metal monochalcogenides (MX) are promising candidate materials for electrochemical desalination owing to their high ion removal capacity and layered ion transport channels, yet suffer from chemical instability and strong interlayer coupling induced by M-atom lone-pair electrons, as well as poor conductivity. Here, we introduce a van der Waals (vdW) wrapping strategy using a periodic vdW superlattice to mitigate these limitations. Using (SnS)1.15TaS2 superlattice as a proof-of-concept, we demonstrate that alternating SnS and conductive 1H-TaS2 sublayers enhance structural stability and charge-transfer kinetics during CDI, while maintaining atomically smooth channels for efficient ion transport. Importantly, this architecture intrinsically encapsulates each SnS layer with 1H-TaS2, dissipating mechanical stresses upon Na+ (de)intercalation and ensuring exceptional cycling stability. This design achieves an ultrahigh NaCl removal capacity of 59.6mg g-1 (500mg L-1 NaCl, 1.2V), surpassing SnS and TaS2 alone by factors of 136.5% and 100%. The desalination performance of (SnS)1.15TaS2 ranks among the best of reported 2D electrode materials. The electrode exhibits an excellent desalination rate of 8.7mg g-1 min-1, and >85% capacity retention over cycling tests. The vdW wrapping strategy establishes a robust design paradigm for high-performance desalination electrodes.