In this study, a hierarchical rod-assembled, polypyrrole-modified Ce–Al–La trimetallic metal–organic framework (Ce–Al–La–MOFs@PPy) composite was successfully synthesized through a solvothermal method combined with in situ polymerization for efficient fluoride removal from aqueous solutions. The incorporation of conductive polypyrrole (PPy) into the multimetallic MOFs effectively enhanced the structural stability, surface properties, and adsorption performance of the material. Adsorption experiments demonstrated that the optimal metal-to-ligand molar ratio was 3:1, and the prepared adsorbent exhibited excellent fluoride removal performance under weakly acidic conditions (pH = 5). The maximum adsorption capacity calculated from the Langmuir model reached 216.92 mg·g−1 at 45 °C. Adsorption kinetics were well fitted by the pseudo-second-order model, indicating that the adsorption process was mainly governed by chemisorption. Mechanism investigations based on FTIR and XPS analyses demonstrated that fluoride removal mainly occurred through electrostatic attraction and coordination exchange between fluoride ions and the Ce/La active sites. In addition, the composite exhibited good selectivity, anti-interference ability toward coexisting ions, and satisfactory fluoride removal performance in practical industrial wastewater. These findings suggest that Ce–Al–La–MOFs@PPy is a promising adsorbent for efficient fluoride-contaminated wastewater treatment.

Low-cost and highly safe aqueous zinc metal batteries (AZMBs) hold great promise as next-generation energy storage systems. However, water-induced side reactions and Zn dendrite growth are recognized as two major challenges hindering the commercial application of AZMBs. Here, we integrate anionic chemistry into a cost-effective cosolvent strategy to address these issues. Specifically, N,N-dimethylformamide (DMF), as a cosolvent, disturbs the hydrogen-bond network among water and alters the Zn2+ solvation structure, thereby reducing water-induced side reactions. The sodium D-gluconate (GAS) with the functional groups (& horbar;COO- and & horbar;OH), as an anionic additive, can preferentially anchor onto the Zn surface. The synergistic effect of the GAS anion in DMF cosolvent can guide the Zn2+ migration and protect the Zn anode. Consequently, with this designed electrolyte, the Zn anodes achieve a lifespan of over 2100 h and a high reversibility with Coulombic efficiency of 99.60%. Furthermore, both the Zn//I2@AC and Zn//MnO2 full cells deliver extended cycling stability alongside superior capacities. This study elucidates the role of solvent chemistry from multi-dimension, providing an insight into the regulation of interfacial kinetics in next-generation aqueous batteries.

To explore cost-effective and efficient adsorbents for phosphate purification from water bodies, two types of magnetic La-based trimetallic oxide nanofibers (La2O3-ZrO2-Fe3O4 and La2O3-CeO2-Fe3O4) were fabricated via the combination of electrospinning and heat treatment technology to address phosphate pollutant from wastewater. The adsorption performance of La2O3-ZrO2-Fe3O4 and La2O3-CeO2-Fe3O4 nanofibers was systematically investigated under diverse conditions, including La/Zr and La/Ce molar ratio, precursor calcination temperature, solution pH, adsorbent dosage, etc. The results indicate that both La2O3-ZrO2-Fe3O4 and La2O3-CeO2-Fe3O4 nanofibers fabricated with a La/Zr and La/Ce molar ratio of 2:1 at 500 °C (labeled as LZF21–500 and LCF21–500 respectively) exhibit optimal phosphate removal performance at pH = 3. Adsorption isotherm studies reveal that the dephosphorization process adhere to the Langmuir model, with maximum adsorption uptakes of 115.87 mg g−1 for LZF21–500, and 95.90 mg g−1 for LCF21–500 at 318 K, respectively. Kinetic explorations indicate that the adsorption data are well-fitted by the pseudo-second-order (PSO) model, implying a chemisorption-dominated monolayer adsorption mechanism for both adsorbents. Thermodynamic analysis revealed that phosphate adsorption onto LZF21–500 and LCF21–500 are spontaneous processes, with negative ΔG0 values across the investigated temperatures. Both adsorbents exhibit excellent selectivity toward phosphate, high adsorption rate, and good recyclability. What's more, both adsorbents exhibit excellent phosphate removal efficiency in actual industrial wastewater. XRD, FTIR and XPS characterizations revealed the dephosphorization mechanisms by both fabricated materials include ligand exchange (inner-sphere complexation), electrostatic interactions, as well as surface precipitation. This research advances our understanding of LZF21–500 and LCF21–500 nanofibers as effective and sustainable adsorbents for phosphate extraction with practical applications in wastewater treatment.

The development of C2H6-selective adsorbents is often constrained by the trade-off between uptake capacity and selectivity. Herein, we report a Zn-based metal-organic framework, Zn-PYCME, featuring one-dimensional channels with periodic bottlenecks generated by alternating cavity-like pore regions and methyl-narrowed windows. This pore architecture provides a confined environment favorable for the adsorption of C2H6 over C2H4. Accordingly, Zn-PYCME exhibits a high C2H6 uptake of 96.1 cm3 g- 1 together with a C2H6/C2H4 (1/1) selectivity of 1.94 at 298 K and 1 bar. Breakthrough experiments confirm efficient C2H6/C2H4 separation, together with facile regeneration and stable performance under humid conditions. Grand canonical Monte Carlo (GCMC) simulations indicate that the preferential adsorption of C2H6 arises from the combined effects of pore confinement and multiple weak interactions with the Lewis-basic sites on the pore walls. These results identify periodic bottlenecks introduced by methyl substitution in one-dimensional channels as a useful design strategy for balancing uptake and selectivity in C2H6-selective adsorbents.

Excessive fluoride and phosphate in water may pose risks to human health and adversely affect the ecological environment. Adsorption methods are considered promising technologies for phosphorus and fluoride removal due to their simplicity of operation, low operational costs, and absence of secondary pollution. However, currently developed adsorbents still face challenges such as low adsorption capacity, poor resistance to interference, and limited selectivity. Herein, La-MOF/UiO-66 layered heterostructures were constructed by controlling the amount of methanol and formic acid with epitaxial growth method. La-MOF/UiO-66 with layered stacking and porous structure possess a synergistic effect of more open metal active centers, synergies in bimetallic centers. For the phosphate and fluoride elimination, La-MOF/UiO-66 exhibits outstanding adsorption performance and a broad applicable pH range. The co-existing ions experiments showed that the common anions had a tiny effect for the adsorption performance, demonstrating a high selectivity performance. This is due to the construction of this heterojunction maximizes the exposure of abundant Zr and La metal active sites within a confined space, thereby multiplying the number of adsorption sites. Furthermore, the abundant aperture structure generated by this structure facilitates substance transfer processes, effectively shortening the migration path of target pollutants into the deeper layers of the adsorbent, thereby increasing the adsorption rate. This research offers a reference for the establishment of MOF-on-MOF heterostructures and contributes to the advancement of eco-friendly adsorbent with potential applications.

Ammonium-ion asymmetric supercapacitor (AASC) has emerged as promising candidates for next-generation energy storage systems due to their environmental benignity, cost-effectiveness, and high safety. However, achieving efficient interfacial charge transfer and robust interfacial kinetics remains a critical challenge for highperformance AASC. Herein, we design a high-quality NiCo2S4/Fe2O3 heterojunction electrode with tailored interfacial engineering to address these issues. The results show that NiCo2S4/Fe2O3 heterojunction forms charge transfer via NH4+ mediation, including Co center dot center dot center dot N-H coordination bond and N-H center dot center dot center dot O hydrogen bond. The bridges coupled with a built-in electric field (BIEF) induced by the work function difference at the p-n heterointerface, synergistically accelerate NH4+ diffusion and reduce charge transfer barrier. As a result, NiCo2S4/Fe2O3 exhibits a remarkable specific capacitance of 838.7 F g- 1 and excellent interfacial durability with 96.6 % capacitance retention after 10,000 cycles. A braided coaxial NiCo2S4/Fe2O3//AC@CNT AASC is constructed to achieve a wide voltage window of 1.8 V and a high energy density of 135.5 Wh kg- 1, along with superior mechanical flexibility and cycling stability (92.5 % retention over 2500 cycles). Our study provides a rational strategy for designing interface-bonding heterojunctions to manipulate charge carriers, paving the way for advanced AASCs in wearable and flexible electronics.

Metal-organic frameworks have attracted considerable interest with the characterization of rich pore structure, high charge mobility, and adjustable structures, but the electrochemical application is limited given the drawbacks of low electrical conductivity. This review summarizes the development of conductive MOFs (C-MOFs), specifically including the efforts to date in the conductive mechanism, design strategies, synthesis methods, model prediction and theoretical calculation and electrochemical applications. The proton transfer, electron transfer, ion transfer mechanisms and the coupling effect in C-MOFs are profoundly explored. By discussing the regulation strategy of each conductive mechanism, the puzzle of poor conductivity can be solved, and the implementation of C-MOFs in the electrochemical field can be extended. Understanding each conductive mechanism in electrochemistry ensures the desired performance and stability in specific applications. Furthermore, future development trends and outlooks are offered, along with challenges to the research gaps and weaknesses in conductive mechanisms research and electronic/electrochemical applications of C-MOFs.

Water pollution with fluoride (F-) has been a public safety issue that brings about an extreme threat to human health and the ecological environment. Two chitosan-based microspheres namely La(OH)3@GCCSx-1 and La (OH)3@GCCSx-2 were designed via a green electrospraying technology using glutaraldehyde as a crosslinking reagent and used as efficient fluoride scavengers. The morphology, crystal structure along with chemical composition of two chitosan-based microspheres were verified through comprehensive characterizations of scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectra (FT-IR), and Brunauer-Emmett-Teller measurements (BET), etc. The surface areas of La(OH)3@GCCS2.5-1 along with La(OH)3@GCCS2.5-2 microspheres were 60.23 and 79.25 m2 g-1, respectively. The defluoridation capacity as well as the selectivity of the two chitosan-based microspheres towards fluoride were evaluated through batch adsorption. The results indicate that the optimal defluoridation conditions by the as-synthesized La(OH)3@GCCS2.5-1 and La(OH)3@GCCS2.5-2 were pH of 3, the molar of La(NO3)3 & sdot;6H2O equal to 2.5 mmol, original F-content of 10 mg L-1, and the oscillating time of 90 min. Simultaneously, the two adsorbents exhibit exceptional F-adsorption selectivity. The defluoridation behavior could be well interpreted by Langmuir adsorption isotherm and Pseudo-second-order (PSO) kinetic model. The optimal defluoridation capacity derived from Langmuir isotherm was 180.99 mg g-1 for La(OH)3@GCCS2.5-1 microspheres and 232.47 mg g-1 for La(OH)3@GCCS2.5-2 microspheres at 298 K, respectively. Thermodynamics investigation signified defluoridation behavior on La(OH)3@GCCS2.5-1 and La(OH)3@GCCS2.5-2 microspheres is spontaneous as well as feasible. The defluoridation ability of La(OH)3@GCCS2.5-1 and La(OH)3@GCCS2.5-2 decreased after 5 times of repeated use. Overall, the novel La(OH)3@GCCS2.5-1 and La(OH)3@GCCS2.5-2 adsorbents own promising application and excellent theoretical guidance for the elimination of fluoride.

High fluoride concentration can cause many severe diseases and pose a certain threat to human health, to ensure the normal concentration in aqueous solution is within the specified threshold. Herein, a bimetallic Ce/Zr-MOFs with excellent adsorption performance was fabricated to eliminate the fluoride. The influences of reaction temperature, solution pH and co-existence ions on fluoride removal efficiency were examined. The outcomes showed that Ce/Zr-MOFs had a high adsorption performance. The adsorption kinetic and thermodynamic investigations indicate that the sorption procedure of fluoride ions conformed to the pseudo-second order model and the Langmuir model. The combination of XRD, XPS, and FTIR characterization reveals that the fluoride elimination mechanisms are electrostatic interactions and ion exchange.

Fluoride pollution is a serious environmental problem that is a risk to human health. Hence, the effective elimination of fluoride is urgent. Herein, a novel trimetallic Zr-La-Ce MOF was fabricated with a hydrothermal method and adapted to eliminate fluoride from water media. Characterization showed that the adsorbent presented a flower-like morphological structure with a large specific surface area of 682 m2 g-1. The adsorption property was further evaluated by examining the impact of fluoride concentration, solution pH, and coexisting anions. The adsorption capacity of Zr-La-Ce MOFs is above 110 mg g-1 at pH 2-9, indicating that Zr-La-Ce MOFs have a wide applied pH range, and the coexisting ions have a tiny impact on the fluoride removal performance, demonstrating an excellent fluoride selectivity. The sorption process adhered well to the Langmuir model and pseudo-second order kinetic model, and the maximum Langmuir sorption capacity was 167.61 mg g-1. Practical application investigation, regeneration performance evaluation, and safety experiments demonstrated that the Zr-La-Ce MOFs had excellent recycling performance, with the treated water lower than 1 mg L-1, and no precipitation of metal ions, which has certain potential for practical application and can provide insights and references for the preparation of multimetal MOFs.

Flexible Zn-air batteries (ZABs) are considered one of the most promising energy storage systems in wearable electronic devices. The key component in the flexible ZABs is the air cathode, which hosts the reversible electrocatalytic oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) to attain long-term stability. In the present work, combining the advantage of the electrospinning technique and biomass-derived heteroatomic porous carbon, Fe2P/Co2P heterojunctions supported on N, P co-doped porous carbon are prepared, exhibiting excellent electrocatalytic OER/ORR performances, which is better than the commercial electrocatalysts based on noble metals. Consequently, the flexible aqueous ZABs as fabricated present remarkable charge and discharge rates, power density, volumetric energy density, folding durability, as well as long-term operational life. By initiating a novel route toward the design and development of air cathode electrode materials, this work paves the way for the practical deployment of flexible ZABs.

The cypress-derived hard carbon (WC-1100) exhibits superior electrochemical performance, which can be attributed to its distinct pore architecture and interlayer spacing optimization.

Phosphate and fluoride ions are common water pollutants whose presence and excessive discharge cause potential hazards to the environment and human health. MOF materials commonly used to remove phosphate and fluoride ions are usually in powder form, with low recovery during regeneration. Herein, to address these issues, Fe3O4@La-Zr-MOFs magnetic composites for phosphate and fluoride removal were fabricated by means of the hydrothermal method. The adsorption properties of the adsorbent were systematically assessed by means of adsorption experiments. The magnetic Fe3O4@La-Zr-MOFs exhibited a magnetic recovery efficiency of 93%, and they could maintain outstanding adsorption performance at a broad range of pH values and superior selectivity for phosphate and fluoride ions. The adsorption process conformed to the Langmuir isotherm and pseudo-second-order models, indicating that it was dominated by monomolecular chemisorption. Further characterization of the Fe3O4@La-Zr-MOFs before and after adsorption and kinetic thermodynamic investigation revealed that the elimination mechanism of phosphate and fluoride ions by Fe3O4@La-Zr-MOFs includes ion exchange, electrostatic interactions, and surface complexation. This study demonstrates that magnetic reusable Fe3O4@La-Zr-MOFs composites have great promise for phosphate and fluoride removal and recovery.

Fe–Ce-MOFs with a rice-grain-like morphology were successfully obtained via hydrothermal synthesis, where ferric chloride (FeCl3) and cerium nitrate [Ce(NO3)3] served as the metal precursors and terephthalic acid (PTA) acted as the organic coordinating ligand. The effects of the Fe:Ce molar ratio, (Fe/Ce):PTA ratio, reaction duration, and synthesis temperature on adsorption performance of the Fe–Ce-MOFs were systematically studied. A comprehensive evaluation was conducted on the removal of fluoride and phosphate ions from aqueous solution. Under optimized conditions, the maximum adsorption capacities of Fe–Ce-MOFs for fluoride and phosphate reached 183.82 mg g−1 and 110.74 mg g−1, respectively. Adsorption data correlated strongly with the Langmuir isotherm, were best represented by the pseudo-second-order kinetic model, and were identified as a spontaneous and endothermic reaction. After three regeneration cycles, the adsorbent still maintained high removal efficiencies for fluoride (85.17%) and phosphate (47.34%) removal. In practical wastewater treatment, removal efficiencies of 92.04% for fluoride and 93.87% for phosphate were achieved. Mechanistic studies revealed that fluoride removal was dominated by electrostatic attraction and hydroxyl–fluoride ion exchange, whereas phosphate removal was attributed to the generation of inner-sphere complexes involving PO43− and Fe/Ce active sites. This study not only elucidates the synergistic mechanism of fluoride and phosphate elimination by Fe–Ce-MOFs but also provides theoretical guidance and application prospects for the development of highly efficient and stable bimetallic MOF-based adsorbents for environmental remediation.

Phosphate pollution caused by human activities has become a pressing environmental issue, leading to eutrophication and severe ecological risks. In this study, artificial humic acid (HA) and fulvic acid (FA) were synthesized from tung fruit and glucose, respectively, and further composited with ferrihydrite (Fh) to prepare HA/Fh and FA/Fh adsorbents for phosphate removal. The structural and morphological characteristics of the composites were confirmed by SEM, XRD, FTIR, and XPS analyses, which indicated successful complexation of HA or FA with Fh through ligand exchange and surface interactions. Batch adsorption experiments revealed that HA/Fh and FA/Fh exhibited significantly enhanced adsorption capacities compared to pristine Fh, with maximum Langmuir adsorption capacities of 33.67 mg g−1 and 37.06 mg g−1, respectively. The adsorption behavior was well described by the pseudo-second-order kinetic model and the Langmuir isotherm, suggesting a chemisorption-dominated process involving ligand exchange between surface –OH groups of Fh and phosphate ions, supplemented by electrostatic attraction. Coexisting ion studies demonstrated that Cl− and SO42− slightly promoted phosphate adsorption, while NO3− and CO32− strongly inhibited it, highlighting the competition of multivalent anions with phosphate for Fe3+ active sites. Importantly, the phosphate-enriched adsorbents can be directly recycled as phosphorus fertilizers, providing a sustainable pathway for both environmental remediation and phosphorus resource recovery.

Polyvinylpyrrolidone (PVP) dispersant was added to Ce/Zr metal-organic frameworks (MOFs), forming needlelike PVP@Ce/Zr-MOFs adsorbents via the hydrothermal method. The effects of solution pH, co-existing ions, reaction temperature, and PVP dosage on the performance of fluoride and phosphate elimination from aqueous solution were examined in batch adsorption experiments. The sorption behaviors were also revealed through adsorption thermodynamic and kinetic studies. The PVP@Ce/Zr-MOFs had an outstanding selectivity over a wide pH range. In addition, they selectively adsorbed phosphate and fluoride ions co-existing with common ions in simulated and real wastewater and maintained high efficiency in the existence of other anions. The sorption procedure was depicted with the pseudo-second order model and the Langmuir model. A mechanistic analysis revealed that fluoride and phosphorus were eliminated by PVP@Ce/Zr-MOFs via exchange interaction with hydroxide ions, electrostatic interactions with charged particles on the adsorbent surface, and the formation of strong inner-sphere complexes of Zr and Ce ions with the target phosphate and fluoride ions.

As a convenient photothermal material, polydopamine (PDA) has been widely utilized in wood-based evaporators. However, the loading conditions of polydopamine on biomass bulk materials have not been systematically studied. In this paper, the suitable reaction conditions of polydopamine were studied with rattan as the substrate, and a reference for the improvement of the loading conditions was proposed. The polydopamine-loaded rattan-based evaporator (PDA-R) prepared on this basis exhibits excellent working stability due to the unique large-scale hierarchical porous structure of rattan. In addition to excellent salt resistance and cycle performance (evaporation rate decays by 5.1% after 30 cycles), the larger-aperture channel (200–450 μm) also brings better adaptability to salinity changes than polydopamine-loaded basswood-based evaporator (PDA-BW) (the attenuation coefficient of PDA-R is 6.2%, while the attenuation coefficient of PDA-BW is 16.3%). All of these indicate the broad prospects of polydopamine-loaded rattan-based evaporator as a multi-effect treatment scheme of brine.

Two metal-organic frameworks Ce-MOFs and Ce/Mn bimetallic MOFs for immobilization of fluoride from the aqueous system have been fabricated. Batch defluoridation studies were performed with varying preparatory adsorbate concentration, pH and contact time. The defluoridation performance remains at a high and stable level within the pH range of 3-7. Based on the competitive adsorption investigation, Ce-MOFs and Ce/Mn bimetallic MOFs had high affinity and anti-interference ability, except that the presence of co-existing ion (PO43-) exerted significant interference. Adsorption isotherm and kinetic researches confirmed that the defluoridation process by Ce-MOFs and Ce/Mn bimetallic MOFs can be simulated by Langmuir model (R-2 > 0.99) and pseudo-second-order kinetic model (R-2 > 0.999), revealing the chemisorption processes for defluoridation. The maximum fluoride uptakes of Ce-MOFs and Ce/Mn bimetallic MOFs derived from Langmuir model were 212.76 and 185.19 mg g(-1) at 323 K. The negative Delta G(0), positive Delta S-0 (100.66 and 102.28 J mol(-1) K-1), and positive Delta H-0 (19.71 and 20.45 kJ mol(-1)) revealed that the adsorption of F- onto the surface of Ce-MOFs and Ce/Mn MOFs was endothermic, spontaneous as well as entropy increase in nature. After three consecutive cycles, both Ce-MOFs and Ce/Mn MOFs stayed good fluoride removal property, indicative of good recyclability. In summary, Ce-MOFs and Ce/Mn MOFs display potential for fluoridation elimination owing to their satisfactory fluoride capture capacities and rapid adsorption speed among lots of adsorbents.

As atenolol overdosing can lead to severe health complications, the rapid detection of atenolol intake in point-of-care settings is highly desirable. The recent advancement of redox analytical methodologies has facilitated the efficacious quantification of these compounds for drug analysis, but their performance still presents challenges in practical applications. This study addresses these challenges by controlling the electropolymerization of polydopamine (PDA) on highly porous laser-induced graphene (LIG) electrodes with enhanced electrochemical redox activity for the detection of drug molecules such as atenolol, with minimized interference with the other active substances to induce variation of electrochemical behavior. The enhanced sensitivity of atenolol is attributed to the superhydrophilicity and increased number of active surface sites and -NH2 groups in the PDA polymer through a controlled polymerization process. Moreover, the simulation results further reveal that highly sensitive sensing of atenolol molecules relies on optimal adsorption of the atenolol molecule on dopamine or dopaminequinone structural units. The resulting sensors with high repeatability and reproducibility can achieve a low detection limit of 80 μM and a sensitivity of 0.020 ± 0.04 μA/μM within a linear range from 100 to 800 μM. The materials and surface chemistry in the electrode design based on highly porous LIG provide insights into the integration and application of future scalable and cost-effective electrochemical sensors for use in point-of-care or in-field applications.

Wood-based electrodes are widely used in supercapacitors due to their renewable and three-dimensional selfsupported properties. Low space utilization of wood-based electrodes seriously restricts its practical applications. In this paper, a wood/phenolic resin composite was designed, which can effectively enhance the space utilization of wood and ensure a hierarchical porous structure. The prepared balsa wood/phenolic resin composite-derived electrode obtained a high areal capacitance (8169 mF cm-2), which is 954 % of pure balsa wood-based electrode. Moreover, the assembled symmetrical supercapacitor device exhibits outstanding electrochemical performance, displaying a high areal capacitance of 3.3 F cm-2, and a competitive volumetric energy density of 2.88 mWh cm-3. More importantly, this design has been successfully used to prepare various species wood-derived electrodes. Therefore, as a general strategy, which gives a novel idea for the design of wood-derived electrodes and may affect other fields using wood-based materials.