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We elucidate the successful harnessing of the atomistic "pump-driven" effect to engineer a potent internal electric field (IEF) within transition metal oxides (TMOs). This IEF acts as a dynamic catalyst for charge transfer, significantly bolstering reaction kinetics and, consequently, augmenting the efficacy of hybrid capacitive deionization (HCDI) systems. [Display omitted] • Successful synthesis of the MoS 2 @MnO 2 heterostructure. • Atomic-level "pump-driven" effect induces a strong inherent electric field. • Meticulous design enhances directional electron transfer and charge efficiency. • Enhanced desalination capacity and rate compared to pristine MnO 2. • Leveraging empirical and computational insights enriches understanding. In addressing the limitations imposed by the inherently low electronic conductivity and substantial ion transfer resistance of transition metal oxides (TMOs) in hybrid capacitive deionization (HCDI) applications, this study delineates a pioneering approach through the fabrication of a MoS 2 /MnO 2 heterostructure, leveraging manganese dioxide (MnO 2) as a model system. The investigation underscores the essentiality of constructing high-quality interfaces to act as conduits for directional charge flow, a critical but formidable challenge for enhancing desalination efficacy in electrode materials. By harnessing an atomistic "pump-driven" mechanism, the MoS 2 /MnO 2 heterostructure demonstrably facilitates the promotion of desalination processes, underscored by the establishment of a potent local electric field (IEF) aimed at commanding charge dynamics. Empirical and computational analyses coalesce to unveil the preferential electron transfer from MoS 2 to MnO 2 , a phenomenon precipitated by charge redistribution. This orchestrated charge flow not only augments electronic and ionic transfer efficiencies but also emboldens the MoS 2 /MnO 2 heterostructure with enhanced desalination capabilities. The results show that MoS 2 /MnO 2 demonstrates superior HCDI performance compared to MnO 2 in a 500 mg L-1 NaCl solution at 1.2 V, with SRC of 33.21 mg g-1 and SRR of 1.50 mg g-1 min-1. The elucidation of this charge-guided dynamic, achieved through meticulous manipulation of the electronic microstructure and the IEF at the atomic scale, presents a novel paradigm for material science. This research presents an innovative approach for realizing robust charge-guided dynamics through the deliberate manipulation of the electronic microstructure and IEF of materials, employing an atomic-level "pump-driven" effect. This strategy opens new avenues for extending these principles to a broad array of advanced materials. [ABSTRACT FROM AUTHOR]

Channel-aligned regulation of photoelectrode within the bulk structure to generate eminent light absorbance and high-level pollutant adsorption is pivotal but challenging for realizing high-performance photofuel cell (PFC) system. Here we demonstrated for the first time the capability of an expansion-flow-modulated DIW 3D printing for controllably constructing porous microlattice photoelectrode with multiscale well-interconnected oriented channels and vertical alignment of photoactive graphene nanosheets, which facilitated remarkable light spreading/absorption and highly efficient pollutant diffusion/trapping, thereby enabling an assembled vertically-aligned PFC (VAPFC) with prominent photoelectric conversion capability for wastewater pollutants under sunlight. [Display omitted] • Porous microlattice photoelectrode was consistently constructed through a controllable and scalable expansion-flow-modulated DIW 3D printing strategy. • 3DP photoelectrode featured multiscale well-interconnected oriented channels and vertical alignment of photoactive graphene nanosheets. • The unique architecture of photoelectrode enabled remarkable light spreading/absorption and highly efficient pollutant diffusion/trapping. • Assembled VAPFC exhibited an impressive photoelectric conversion capability for wastewater pollutants under sunlight. Channel-aligned regulation of photoelectrode within the bulk structure to generate eminent light absorbance and high-level pollutant adsorption is pivotal but challenging for realizing high-performance photofuel cell (PFC) system. Herein, we demonstrated an effective and scalable expansion-flow-modulated direct ink writing (DIW) 3D printing strategy for controllably constructing microlattice photoelectrode, with multiscale well-interconnected oriented channels built by layer-by-layer highly-regular assembly of filaments and vertical alignment of graphene nanosheets within filaments as well as uniform coupling of abundant photoactive nanoparticles to highly ordered channel walls. The unique architectural features enabled high-speed and effective diffusion/trapping of wastewater pollutants throughout the entire photoelectrode, and meanwhile facilitated ready spreading of incident light into the photoelectrode interior to yield high light absorption. As a result, an integrated 3D-printed vertically-aligned PFC (3DP VAPFC) assembled with as-fabricated photoelectrode exhibited its powerful capability for efficiently converting wastewater pollutants into electric energy under sunlight, with remarkable cycling stability and maximum power density of 0.11 mW cm−2. This work opens a promising route for architecting advanced photoelectrode toward PFC devices with highly efficient degradation and electricity generation of pollutants. [ABSTRACT FROM AUTHOR]

[Display omitted] • MBiC@tE achieves an efficient F- electrosorption capacity of 37.9 mg F - gelectrode-1. • Fluoride was removed by the synergistic roles during capacitive control process. • Bismuth active units induced Faradaic redox reaction and increased pseudocapacitance. • The complex carbon framework ensured electrical double layer capacitance. • Insights into the phase transition of bismuth during the electrosorption. Remediation of fluoride in groundwater through electrosorption to cope with its high charge density and the smallest anion radius remains a promising strategy. Composite carbon materials obtained by calcining metal–organic frameworks contribute to the performance of conventional fluoride electrosorption systems. This study provides a redox-active electrode (MBiC@tE) that incorporates the Faradaic ion trapping effect for fluoride removal. Under potential control, MBiC@tE reversibly traps/releases fluoride anions from the aqueous solution through the combined roles of Faradaic pseudocapacitance and electrical double layer capacitance, with an electrosorption capacity of approximately 37.9 mg F - g electrode -1. The target contaminant anions are directly involved in the Faradaic reaction on the bismuth sites, with the formation of Bi-F bond excited by an electric field, thus resulting in the removal of fluoride as a consequence of the generation of insoluble substance (BiF 3). Furthermore, as expected (Bi 0 + 3F- ⇌ BiF 3 + 3e-), the working electrode exhibits good reversibility and maintains a high fluoride removal capacity even after multiple cycles. This study presents a comprehensive elucidation on the synergistic roles of Faradaic effect and electrical double layer capacitance induced by the electric field, and offers profound insights into the phase transition of bismuth and its affinity for fluoride during the electrosorption. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fluoride (FL) is abundant in the earth's environment and is often discharged into aquifers. • Fluorosis is the outcome of continuous exposure to FL concentrations of more than 4 ppm. • CM for FLR have a long lifespan and are highly resistant to harsh conditions. • EDI for FLR shows a reduction in labor costs and no chemicals required for resin regeneration. • MCDI offers significant potential for the removal of organic pollutants including fluoride. One of the biggest issues facing the globe today is fluoride poisoning of water, which is a severe risk to the well-being of people since water is essential for consumption from both natural and man-made sources. Fluoride in water can be removed using a variety of methods, although the issue is still not completely solved. Because of its ionic size and reactivity, fluoride can be hard to remove from water-based solutions using traditional electrochemical, precipitation, and adsorption methods. One of the latest innovations that has been shown to be highly successful in bringing fluoride levels down to the required levels is the use of membranes. This review discusses fluoride and its characteristics, sources, impacts on the environment and humans, fluoride measurement techniques, and fluoride applications. The efficacy of different types of membrane separation processes are covered with respect to techniques developed, advantages and drawbacks of defluoridation processes. This review critically examines membrane-based techniques for different defluoridation processes including nanofiltration (NF), reverse osmosis (RO), membrane distillation (MD), electrodialysis (ED), and forward osmosis (FO). Furthermore, the study addresses developments in ceramic membranes, electrodeionization and membrane capacitive deionization, hybrid membrane techniques, and life cycle assessment (LCA) for membrane-based defluoridation process. The work meets the SDGs goal #6 of clean water supply. [ABSTRACT FROM AUTHOR]

• A knittable fiber-shaped capacitive pressure sensor was prepared. • The knittable sensor can be seamlessly incorporated into garment. • The knittable sensor showed a sensitivity of 0.04 kPa−1 in low pressure range. • The sensor's easy-integration facilitates real-time rehabilitation monitoring. The integration of sensors into clothes offers significant convenience for monitoring the rehabilitation of patients. However, conventional flat sensors face challenges in achieving seamless integration due to their incompatibility with clothing. Here, we created a knittable fiber-shaped capacitive pressure sensor designed for long-term monitoring of shoulder movements of patients with rotator cuff injuries. This innovative sensor incorporates copper wires and silver conductive fibers as electrodes, with a polyvinylidene fluoride (PVDF) composite fiber membrane containing zeolite imidazolate framework (ZIF-8) particles as the dielectric layer. The resultant sensor can be seamlessly while non-invasively incorporated into the garment of patents due to its exceptionally flexibility. After optimizing the number of Cu wires (4) and electrospinning time of PVDF (8 min), the knittable sensor showed a sensitivity of 0.04 kPa−1 in the range of 2–8 kPa, 10 times higher than that without ZIF-8 (0.003 kPa−1). Beyond its applications in monitoring shoulder movement across various directions and degrees, this sensor has proven its ability in monitoring breath or recording weight when encompassed into a mask or a carpet, respectively. Via integrated in daily wearings, this sensor holds immense potential in the fields of rehabilitation monitoring and personal health management due to its remarkable sensitivity and flexibility. [ABSTRACT FROM AUTHOR]

[Display omitted] • Core-shell heterostructured CoFe@NiFe PBA is successfully synthesized. • Encapsulation of CoFe PBA with NiFe PBA shell alleviates dissolution of the core material during Na+ insertion/extraction. • Favorable hydrophilicity and large specific surface area of the shell material promotes accessibility of electrolyte ions. • Higher electrical conductivity of the shell material enhances charge transfer on the electrode. 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. [ABSTRACT FROM AUTHOR]

[Display omitted] • The sandwich structure NPC/NiMn-LDH/MXene is elaborately designed for Cl- capture. • The NPC/NiMn-LDH/MXene electrode presents optimized Cl- diffusion kinetics. • The NPC/NiMn-LDH/MXene//NPC cell showcases exceptional Cl- removal performance. • DFT results validate NPC/NiMn-LDH/MXene facilitates interfacial charge transfer. Layered double hydroxides (LDHs) have been recognized as prospective two-dimensional capacitive deionization (CDI) faradaic materials for Cl- capture, offering tunable interlayer distance, high anion exchange capacity, and reversible ion intercalation/deintercalation ability. However, the self-stacking tendency, poor electrical conductivity, and undesired stability of LDHs nanosheets severely impede ion migration and active sites accessibility, leading to unsatisfactory CDI performance. Herein, we present an elaborately designed three-dimensional sandwich structural composite N-doped porous carbon spheres/NiMn-layered double hydroxide/MXene (NPC/NiMn-LDH/MXene) to efficiently capture Cl- as the CDI anode. In this assembly, MXene not only ensures excellent electrical conductivity for rapid ion transfer but also serves as a robust substrate for the uniform dispersion of NiMn-LDH nanosheets. Moreover, NiMn-LDH effectively inhibits the agglomeration of MXene and provides substantial storage capacity for ion accommodation. The conductive intermedium NPC establishes interconnected conductive channels, enriching accessible charge transport pathways, resulting in an accelerated ion diffusion kinetics. Accordingly, the NPC/NiMn-LDH/MXene electrode demonstrated predominant specific capacitance (265 F g-1), lower ion transfer resistance, and an optimized Cl- diffusion coefficient (7.95 × 10-17 cm2 s−1). In an asymmetrical CDI cell assembly, the NPC/NiMn-LDH/MXene//NPC cell delivered outstanding Cl- removal capacity (43.5 mg g−1), swift salt removal rate (12.5 mg g−1 min−1), efficient energy utilization (0.183 kWh kg−1-NaCl), and remarkable cyclic adsorption/desorption stability (89.6 % retention rate). Additionally, density functional theory (DFT) calculations validated that the sandwich construction of NPC/NiMn-LDH/MXene facilitated interfacial charge transfer from NPC and MXene to NiMn-LDH, accelerated ion transfer rate, and reduced ion migration energy, resulting in accessible ion diffusion kinetics and smooth Cl- shuttle. This unique approach enriches ion transfer pathways by leveraging the distinctive structural characteristics of faradaic materials, providing valuable insights for further developments in CDI technology. [ABSTRACT FROM AUTHOR]

• A novel capacitive deionization with a three-phase architecture (T-CDI) was proposed. • Cathodic oxygen reduction was enhanced in T-CDI without affecting desalination. • SAC value and H 2 O 2 generation were 14.91 mg/g and 25.55 mg/L, respectively. • Simultaneous desalination and organics control was achieved by T-CDI/UV. • Applicability of T-CDI in long-term operation was investigated. Cathodic oxygen reduction, as a Faradaic side reaction, has been proven to be thermodynamically favorable for H 2 O 2 generation in capacitive deionization (CDI), which may provide a greener manner for organics control alongside desalination. However, the low levels of dissolved oxygen (DO) in saline water and its potential Faradaic degradation of carbon-based electrodes limit the H 2 O 2 generation in the conventional CDI (C-CDI). Herein, a novel three-phase CDI architecture (T-CDI) was proposed to simultaneously achieve stable desalination and supplementary H 2 O 2 generation. Unlike C-CDI architecture, T-CDI was open-ended at the cathode side, where porous nickel foam was used as current collector and air diffusion layer. Accordingly, a stable gas–liquid-solid three-phase interface was created inside the cathode, thus enhancing the diffusion and utilization of atmospheric air and preventing the damaging effects of excessive DO on the electrode. A stable electrosorption and electrocatalysis performance for T-CDI was obtained by regulating electrode hydrophilic-hydrophobic properties, comparing with other CDI configurations, and altering operating conditions. The salt adsorption capacity and H 2 O 2 accumulative concentration were 14.91 mg/g and 25.55 mg/L, respectively. Furthermore, the simultaneous desalination and organics control in T-CDI were investigated with the assistance of UV irradiation (T-CDI/UV). When treating NaCl and sulfamethazine (SMR) mixture solution, T-CDI/UV significantly reduced the irreversible electrode organic fouling and improved the desalination stability. Additionally, the potentially hazardous SMR was effectively removed alongside desalination. Finally, the long-term operation of T-CDI demonstrated that the generated H 2 O 2 cannot induce an additional substantial deterioration in desalination stability. The techno-economic assessment showed T-CDI was economically competitive compared with C-CDI. This study provides insights into the synergy of non-Faradaic and Faradaic processes and further diversifies the application of CDI in water treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • A CNT-CeO 2 electrode is fabricated to selectively remove F− in mixed ion solutions. • CNTs increase the conductivity of the electrode and hinder the aggregation of CeO 2. • Pseudo-capacitance behavior of F– entering CeO 2 was observed first time by EQCM. • The energy consumption for treating actual groundwater using scaled-up equipment is low at approximately 0.2 kWh/m3. Selective capacitive deionization (SCDI) is a promising process for preferentially removing specific ions from waters with complex compositions. The selectivity towards certain species in CDI is most frequently achieved through novel electrode materials with high affinities towards targeted species. In this study, we investigate the selective removal of fluoride ions from groundwater containing concentrated co-existing chloride ions. A carbon nanotube-CeO 2 (CNT-CeO 2) electrode is employed for the electro-sorption of fluoride ions. Our findings are compelling: when processing a mixed F−/Cl− solution comprising 10 mg/L F− and 100 mg/L Cl−, the CNT-CeO 2 electrode is seen to reduce the concentration of F− ions to 1.5 mg/L in just 150 min, amounting to an 85 % F− removal efficiency, while the Cl− removal efficiency remains below 2 %. Importantly, this translates to a F−/Cl− separation factor of up to 4.16 when using the CeO 2 -based electrodes, which is 40 times higher than that achieved with conventional activated carbon (AC) electrodes. Furthermore, the energy consumption for treating actual groundwater using scaled-up equipment is impressively low at approximately 0.2 kWh/m3. The high affinity of CNT-CeO 2 towards fluoride is attributed to the intercalation Faraday capacitance initiated by the reaction between F− with CeO 2 , as verified by the electrochemical quartz crystal microbalance (EQCM). Moreover, EQCM results show a substantial increase in both mass and current as the potential increased beyond 0.8 V vs Ag/AgCl, implying that the current surge is not a result of water splitting but rather the adsorption of F− onto the CNT-CeO 2 electrode. The addition of CNTs substantially increases the conductivity of CeO 2 electrodes and restricts the aggregation of CeO 2 , thereby accelerating ion diffusion and promoting selective adsorption characteristics. Importantly, our electro-driven approach demonstrates excellent adsorption–desorption over 20 cycles. This comprehensive study advances the technological development of selective CDI, while providing new insights for fluoride removal in groundwater. [ABSTRACT FROM AUTHOR]

Bithmush-impregnated carbon nanofiber aerogel with a rational "multi-layer protection" shell was unprecendently prepared and used as chloride chloride-capturing electrode to trigger fast and ultra-durable faradic capacitive deionization. [Display omitted] • Bi nanoclusters impregnated carbon nanofiber aerogel (Bi NCs@CNFAs) was prepared. • Bi NCs@CNFAs was unprecedently introduced in faradic capacitive deionization (FDI). • The multi-layer protection design could prevent structural changes of Bi NCs@CNFAs. • The ultrasmall and even distributed Bi nanoclusters enable fast pseudo-capacitance. • The desalination rate/durability of our FDI outperforms most reported systems. Faradic-based capacitive deionization (FDI) has been recognized as one of the most promising technologies to solve the freshwater crisis, yet was hindered mostly by the relatively low desalination rate and sluggish long-term stability of its anode materials. Through careful analysis, the origin of the slow desalination rate was determined to be the faradic diffusion and mass transfer, while the poor cycling stability could be originated from the volumetric expansion of the redox-active material as well as structural damage caused by the uneven stress during multicycle operation. Herein, we developed a Bi nanocluster (NCs) embedded in carbon nanofiber aerogels (Bi NCs@CNFAs) nanostructure as chloride-capturing electrodes for FDI. The essence of this work lies in the design of the "multi-layer protection" shell that could not only limit the volumetric expansion of the Bi NCs (inner protection layer) but also alleviate the stress caused by potential structure changes (outer buffer layer). As a result, the Bi NCs@CNFAs-based FDI display ultra-fast desalination kinetics (0.524 mg g−1 s−1) with remarkable long-term stability (only 8 % reduction over 250 cycles), significantly outperformed the highest value reported in the literature so far. This study is interesting because it exemplifies the significance of problem-driven strategy (nanocluster-induced surface-driven capacitance to address slow desalination kinetics; rigid carbon shell to suppress the volumetric expansion of Bi NCs; CNFAs scaffold to address potential structural damage and aggregation) to improve the desalination performance of FDI, which could further motivate advancements of highly effective desalination systems in the future. [ABSTRACT FROM AUTHOR]

[Display omitted] • LVP@2C exhibited a maximum Li+ adsorption capacity of 25.8 mg g−1 in 200 mg L−1 of Li+ ion solution. • The LVP@2C maintained a high retention rate of 78 % even after 50 cycles. • The selectivity coefficient of LVP@2C is 444.7 and 351.2 at Mg/Li ratios of 1:5 and Na/Li ratios of 1:15. • The LVP@2C displayed excellent lithium extraction performance in natural Tibet salt lake brine. • The Li+ adsorption and desorption behavior is due to V reversible synergistic valence transitions. Recently, with the rapid development of lithium-ion batteries and electric vehicles, the demand for lithium resources in the world has undoubtedly greatly intensified. Based on the advantages of high selectivity and low energy consumption, capacitive deionization (CDI) technology is well-suited for the selective extraction of lithium resources from salt lakes. Herein, carbon-coated Li 3 V 2 (PO 4) 3 (LVP@C) is developed as a cathode electrode for the first time by using a hybrid CDI device to selectively extract Li+ ions from salt lake brine, due to its high theoretical capacity and excellent cycling capacity. The electrochemical (de)intercalation mechanism of Li+ ions in the LVP@C has been evaluated by electrochemical, X-ray photoelectron spectroscopy (XPS), and in-situ X-ray diffraction (XRD) techniques, demonstrating a reversible transition of the V valence state during electrosorption/desorption based on Faradaic redox reaction. The optimized LVP@2C delivers a maximum Li+ electrosorption capacity of 25.8 mg g−1, and still maintains a high retention of 78 % even after 50 cycles. The LVP@2C has lithium selectivity coefficients of 444.7 and 351.2 at high Mg-Li ratios of 1:5 and high Na-Li ratios of 1:15. Density Functional Theory (DFT) calculations further reveal that the selective electrosorption mechanism in the LVP@2C electrode is mostly ascribed to the smaller hydrated ionic radius and lower ionic diffusion energy barrier of Li+ ions in comparison with Mg2+ ions. Finally, the effectiveness evaluation of the lithium selective extraction from the brine of a natural salt lake in Tibet indicates that the LVP@2C has highly selective electrosorption of lithium (α (Li/Mg) = 187.50, α (Li/K) = 136.11, α (Li/Na) = 116.88, α (Li/Ca) = 4.92) and can serve as a potential electrode for the extraction of lithium from salt lake brine. [ABSTRACT FROM AUTHOR]

A highly water-sources tolerant monolithic H+/10-CoMoB catalyst has been successfully developed by simple and efficient H+-etching corrosion engineering. The catalyst enables high water-sources adaptive hydrolysis of borohydrides. Moreover, NaBH 4 -based H 2 supply system with this catalyst has achieved full drive of 100 W fuel cell using different water-sources. [Display omitted] • CoMoB based catalyst with high water-sources adaptability has been developed. • The catalyst has great borohydride hydrolysis activity in natural water-sources. • H 2 generator with the catalyst drives 100 W fuel cell using various water-sources. High water-source adaptability is meaningful to the popularization of hydrolysis of borohydrides as portable hydrogen generation technique. Herein, the key catalyst that can enable high water-sources adaptive hydrolysis of borohydrides is successfully developed for the first time. The as-prepared monolithic CoMoB based catalyst has outstanding catalytic activity with high hydrogen generation rate of the 3.0 L min−1 g−1 at 25 °C and low activation energy of 38.7 kJ mol−1 toward the hydrolysis of NaBH 4 using deionized water. More importantly, the catalyst exhibits distinguished durability toward hydrolysis of borohydrides in various water, including deionized water, lake water, and even seawater benefiting from its unique structure and gas scouring effect. Furthermore, an efficient NaBH 4 -based H 2 supply system is developed with the catalyst and this system successfully achieves full drive of 100 W fuel cell using different sources of water. This study may provide a new protocol to develop portable H 2 generation system with high water source adaptability in wild environments. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel edge-N doped hierarchical carbons were firstly reported for P electrosorption. • The edge-N strategy endowed more accessible active centers and conductive efficiency. • The LNPC900 electrode showed a superior phosphate removal capacity of 533.06 mg g−1. • The system performed well in natural water purification with low P concentration. • The coupling of electrical capacitance and chemical interactions were achieved. Achieving high-efficiency removal of phosphate has been an urgent issue to combat eutrophication and meet ever-stricter emission standards. Electro-assisted adsorption, a mild electrochemical technology, demonstrated great potential for wastewater treatment owing to the merits of considerable removal performance, facile operation, and energy efficiency. Exploring and boosting the properties of electrode materials is exceedingly vital for technological advancement. In this study, the novel edge-N decorated La-doped hierarchical carbon composites (LNPCs) were developed via in-situ nucleation and one-pot pyrolysis strategy as phosphate capture electrodes. The LNPC900 electrode exhibited an ultrahigh phosphate removal capability of 533.06 mg PO 4 3- g−1 at 1.2 V, surpassing most of the reported electrode materials. Furthermore, this electrochemical system also performed well in the purification of natural river water with low phosphate concentration, where the treated concentration was below the first-class emission standard in China (0.5 mg P L−1). Comprehensive analysis and theoretical calculations indicate that the synergistic property of edge-N and small graphitic carbon nanodomains ensured more accessible active centers and conductive efficiency. The superb phosphate removal capability mainly originated from the coupling contribution of the electrical double layer capacitance, ligand exchange, and electrostatic attraction. This study possesses insight into the theoretical basis for the practical application of phosphate electrosorption and provides a new level of the technology. [ABSTRACT FROM AUTHOR]

[Display omitted] • 3D PAA/GO aerogel was a CDI electrode material. • The double "O" in C = O = C = O acts as a charge transfer and activation site. • The maximum UO 2 2+ adsorption capacity of PAA/GO was 898.7 mg g−1. • DFT explores mechanisms of action. The extraction of uranium is crucial for sustaining a consistent nuclear fuel cycle, yet the task of isolating uranyl ions from aqueous solutions presents formidable challenges. Herein, a PAA/GO aerogel was developed using polyacrylic acid-functionalized graphene, wherein the C = O = C = O segment's dual oxygen served both as electrodes for capacitive deionization and as sites for charge transfer and uranyl capture, effectively purifying uranium mine wastewater. Furthermore, under the stringent experimental conditions set at 298 K and a pH of 5.5, the PAA/GO composite demonstrated an impressive adsorption capacity of 898.7 mg g−1. When this composite was further amalgamated into the CDI architecture, it exhibited an impressive 92 % uranium extraction from genuine mine effluent at an unwavering potential of 0.9 V. Through density functional theory (DFT) analyses, the adsorption energies of [UO 2 (H 2 O) 5 ]2+ with the PAA/GO composite involving C = O = C = O ligands displayed the highest value compared with PAA and PAA/GO composite (involving monodentate and bidentate ligands). The Bader charge analysis further indicating the greatest charge loss in the uranium ion. In conclusion, the novel PAA/GO aerogel 3D framework with its specific C = O = C = O regional chain sets a pioneering standard in uranium extraction techniques, showcasing unprecedented efficiency in UO 2 2+ removal from aqueous solutions. [ABSTRACT FROM AUTHOR]

A vertically oriented porous PVA hydrogel and PDA/CB modified 3D raised-fabric are innovatively designed as an solar evaporator to enhance the evaporation rate, conversion efficiency and self-desalting performance. [Display omitted] • A super water transport PVA hydrogel and PDA/CB modified 3D raised-fabric are innovatively designed as solar evaporators. • It exhibits high water evaporability (1.73 kg m-2h−1, 1 sun) and conversion efficiency (91.9 %). • The 3D raised-fabric solar evaporator system can be readily fabricated for scalable production. • The collected water is in full compliance with the drinking requirements of WHO and EPA. A solar evaporator with simple fabrication process, exceptional photothermal conversion efficiency and dependable continuous water evaporation holds significant potential for seawater desalination and wastewater treatment. Despite the substantial research dedicated to developing high-efficiency solar evaporators, there remains a need for additional exploration to tackle concerns such as salt crystallization, low evaporation efficiency, poor durability and stability. Here, an efficient water transport PVA hydrogel (water transport layer) and polydopamine/carbon black modified 3D raised-fabric (photothermal layer) are innovatively designed as solar evaporators. The synergistic effect between the periodic raised structure and polydopamine/carbon black results in outstanding photothermal conversion capabilities of PDA/CB@RF. Meanwhile, the porous structure of PVA hydrogel and its vertically aligned channels facilitate ion exchange and ensure a consistent water supply to the photothermal layer. This phenomenon serves to prevent the accumulation of salt in the photothermal layer, thereby markedly enhance the water evaporation capability of the PDA/CB@RF evaporator. The results demonstrate that the PDA/CB@RF evaporator system exhibits excellent photothermal conversion performance with its surface temperature rapidly ascending to 73.3 ℃ under 1 sun light intensity, and effectively boost the water evaporation rate (1.73 kg m-2h−1, 1 sun). Furthermore, the PDA/CB@RF evaporator exhibits excellent conversion efficiency (91.9 %) and self-desalting capability. Overall, this solar evaporator system with a 3D raised fabric design integrates light and thermal energy, consistent water evaporation and self-desalting functionalities, which makes it hold the potential to solve the pressing challenge of water shortage. [ABSTRACT FROM AUTHOR]

[Display omitted] • The development history of capacitive deionization for defluorination is introduced. • Recent advances of electrode materials have been classified and reviewed. • Defluorination mechanisms have been summarized. • Challenges for engineering applications are presented. • Future perspectives on defluorination by capacitive deionization are provided. The combined need for advanced treatment of fluoridated water and low-energy technologies has inspired researchers to develop more efficient and green methods of fluoride removal. Capacitive deionization (CDI), a novel water treatment technology, has garnered significant attention in the defluorination field due to its exceptional ion selectivity. Recent decades, CDI has achieved remarkable advancements in electrode materials, F− storage mechanisms, and the potential for engineering applications in the realm of F− removal. However, there has been a lack of reviews that highlight design strategies for electrode materials in terms of fluoride ion properties in water and provide insights into key factors for designing CDI structures with excellent performance and promise for scale applications. Herein, starting from the background of fluorine pollution in surface water, and the selective removal of fluorine heavily relies on the crucial role played by electrode materials. Accordingly, all kinds of defluorinated electrode materials are reviewed. Secondly, the defluorination mechanism is summarized especially the distinctions among these processes. Additionally, the challenges existing in the promotion of CDI defluorination to large-scale applications are firstly analyzed in depth. Finally, future research opportunities and prospects by CDI for defluorination are proposed. In summary, CDI shows great potential for removing fluoride ions from water, offering a fresh approach to sustainable water resource management and environmental protection. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mn dopant-reinforced NaTi 2 (PO 4) 3 possesses superior structural stability and conductivity. • The optimal NT 1.5 M 0.5 P exhibits ultrahigh salt removal capacity of 128.5 mg/g and cycle stability. • The ultrahigh durability is rooted from the solid-solution reaction induced by Mn-ions pillar. • NT 1.5 M 0.5 P||NaFeHCF rocking-chair desalination battery owns stable, rapid and low energy consumption desalination. Battery deionization (BDI) technique has attracted great attention as a potential candidate to tackle the freshwater crisis, but its application is plagued by the lack of electrode materials with large desalination capacity and excellent durability. Herein, Mn dopant-reinforced NaTi 2 (PO 4) 3 (NT 2–x M x P) composites with significantly enhanced structural stability and electronic/ionic conductivity were fabricated toward seawater desalination. Especially, the NT 1.5 M 0.5 P exhibits excellent desalination performance, affording a salt removal capacity (SRC) of 128.5 mg/g with a salt removal rate (SRR) of 18.4 mg g−1 min−1 and almost no capacity attenuation after 500 cycles. Furthermore, the NT 1.5 M 0.5 P further possesses favorable technical feasibility in different aqueous media, including desalination at various NaCl concentrations, temperature, solution pH, and natural seawater. Mechanism studies reveal that the NT 1.5 M 0.5 P undergoes a solid-solution reaction based on the reversible electrochemical reaction of the Ti4+/Ti3+ redox pair during the desalination/salination process. A rocking-chair desalination battery consisting of NT 1.5 M 0.5 P and NaFeHCF demonstrates a favorable desalination ability (average SRC of 49.4 mg/g and SRR of 1.73 mg g−1 min−1), outstanding cycling stability (92 % of capacity retention in 100 cycles), low energy consumption (0.288 kWh/kg-NaCl) and high average charging efficiency (86.9 %). This work sheds light on the rational design of advanced NASICON-type electrodes for seawater desalination with remarkable desalination capacity and long serving life. [ABSTRACT FROM AUTHOR]

• A photoinitiator-grafted polymer chain (PGPC) is synthesized. • PGPC-coated hydrogel demonstrates strong resistance to swelling and drying. • PGPC-coating preparation methods are simple and versatile. • This strategy does not leave residues in the bulk hydrogel. Currently, diverse hydrogels with multiple functionalities have attracted considerable attention. However, due to poor adaptability in real-life application scenarios for example in drying air and underwater, the hydrogels developed to date have not yet realized most of their promising applications, particularly in flexible electronics. Herein, inspired by the process of preparing the outermost layer of sugar coating on Tanghulu, a traditional Chinese winter snack, we report a dipping-ultraviolet (UV) encapsulation method for affording hydrogels with excellent water retention and anti-swelling capacity. A photoinitiator-grafted polymer chain (PGPC) with UV curing capability is prepared by 4-benzoylphenyl acrylate (ABP) and hydrophobic monomers radical polymerization, which is uncrosslinked during synthesis. After dipping and UV irradiation, the PGPC on the polyacrylamide (PAAm) hydrogel surface is cross-linked by benzophenone (BP) chemistry to form a coating network. Furthermore, the PGPC-coated hydrogel PAAm demonstrates great anti-drying properties with a weight fraction of up to 0.85 ± 0.02 after 21 h at 50 °C and anti-swelling capacity with a weight fraction of down to 1.01 ± 0.01 after 120 h in deionized water. Benefiting from the BP chemistry, the versatility of this method is demonstrated using various hydrogels such as polyvinyl alcohol (PVA) and polyzwitterionic hydrogel. As a proof-of-concept, the coated-hydrogel-based sensor shows strong signals anti-interference ability in ambient air and underwater. This work provides a promising route for encapsulating different hydrogels endowing weak hydrogels with strong environmental adaptability. [ABSTRACT FROM AUTHOR]

[Display omitted] • A parametric investigation of the electrochemical desalination cell was carried out. • The longer residence time of the flow electrode and the feed water augmented the desalination. • Surface area of carbon and redox couple play a crucial role in desalination. • A reduction of 235 mg/L of total dissolved solids in tap water was observed. Flow Electrode Capacitive Deionization (FCDI) is a promising technology that uses carbon materials as flow electrodes in aqueous conditions to enable continuous desalination. In this work, the parametric investigation of the FCDI cell was carried out for low and high surface area activated carbon. When 1 mM/1 mM ferri-/ferrocyanide redox couple in the 1 M NaCl supporting electrolyte containing the 5 wt% high surface area activated carbon and 0.5 wt% MWCNT is circulated as flow electrode at the flow rate of 8 mL/min in the electrode chamber and 0.1 mM NaCl feed water is circulated in single-pass mode at 8 mL/min, the FCDI system achieved a significant improvement in desalination performance up to 76.38 % of SRE, with a high average salt removal rate of 43.925 µg/cm2s @ 2 V, charge efficiency of 20.11 % and average energy consumption of 0.27 kWh/mol, through a thorough parametric investigation. When the FCDI cell was tested with tap water, the average salt removal rate, average energy consumption, and salt removal efficiency were calculated at 6.11 μg/cm2s, 2.46 kWh/mol, and 46.61 % respectively, resulting in the reduction of total dissolved solids of 600 mg/L at the inlet to 365 mg/L at the outlet. The combination of microporous high surface area carbon and ferro-ferri redox couple propelled the desalination performance in comparison with the macroporous low surface area carbon, maximizing the ion removal rate, which further reduced the energy consumption and operating voltage for the process. [ABSTRACT FROM AUTHOR]

[Display omitted] • RuO 2 /CeO 2 heterojunction loaded on carbon spheres (RuO 2 /CeO 2 @C) is prepared. • Theoretical calculations investigate the electrocatalytic mechanism of RuO 2 /CeO 2 @C. • RuO 2 /CeO 2 @C exhibits durable water splitting in acidic conditions. The use of proton exchange membrane (PEM) hydrolysis technology holds promise for eco-friendly hydrogen production using renewable energy sources. However, developing efficient, cost-effective, and durable bifunctional electrocatalysts for the acidic oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) remains challenging. Here, we synthesized RuO 2 /CeO 2 heterojunction loaded on carbon spheres (RuO 2 /CeO 2 @C) via hydrothermal and annealing techniques to address this issue. Our experiments demonstrate exceptional catalytic activity of RuO 2 /CeO 2 @C for both OER and HER, with overpotentials of 170 and 120 mV, respectively, at 10 mA/cm2 in 0.5 M H 2 SO 4. Moreover, the electrocatalyst enables overall water splitting at 1.54 V and maintains stability for over 100 h at 10 mA/cm2. Density functional theory (DFT) calculations suggest that RuO 2 /CeO 2 heterojunction modifies d-band center of Ru, balances H adsorption/desorption behavior, accelerates reaction kinetics, and lowers the energy barrier, thereby enhancing electrocatalytic activity. These findings provide valuable insights for future efficient bifunctional water splitting electrocatalyst design. [ABSTRACT FROM AUTHOR]