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Herein, a practical and simple calcination method was used to synthesize layered double oxides (denoted as LDO) and layered double oxides/carbon dots nanocomposites (denoted as LDO-C) for U(VI) efficient removal. The U(VI) adsorption on LDO and LDO-C were investigated under various experimental conditions, and the results indicated that U(VI) uptake on LDO and LDO-C were consumingly dependent on pH and ionic strength at pH > 6, and independent of ionic strength at pH < 6. The adsorption processes of U(VI) on LDO and LDO-C were spontaneous and endothermic, and well simulated by pseudo-second-order model. The maximum adsorption capacity of U(VI) on LDO-C was calculated to be 354.2 mg/g at pH = 5.0 and T = 298 K, which was significantly higher than that of U(VI) on LDO (237.6 mg/g). Particularly, BET, F T-IR, XPS and EXAFS analysis suggested that the higher adsorption capacity of LDO-C was mainly attributed to higher specific surface area and more abundant surface oxygen-containing functional groups (e.g. C-OH), and the main interaction mechanisms were surface complexation and electrostatic interactions. In addition, LDO-C also showed higher adsorption capacity of 241 Am(III) than LDO. All in all, the efficient removal performance and superior versatility of LDO-C indicated that it could be applied as promising candidate for efficient immobilization of radioactive pollutant in environmental pollution management. [ABSTRACT FROM AUTHOR]

Graphical abstract A novel arginine modified hydroxyapatite carbon microsphere (C@HAp/Arg) composite were synthesized by a facile and green method and exhibited superior adsorption efficiency for removal of U(VI). Abstract Uranium was not only the main source of nuclear energy but also one of the long-lived radionuclide. Herein, a novel arginine modified hydroxyapatite carbon microsphere composites (defined as C@HAp/Arg) obtained promptly via a one-step mild hydrothermal method, was applied to remove U(VI) from aqueous solutions. Based on the characterization of transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transformed infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), the synthesized C@HAp/Arg presented globular morphology and abundant functional groups (e.g., COO−), which were beneficial to its combination with U(VI). The interaction mechanism and removal capability of U(VI) on C@HAp/Arg were studied by batch adsorption technique and spectroscopy analysis. The results implied that U(VI) can form strong surface complexes on C@HAp/Arg. The kinetics adsorption of U(VI) followed pseudo-second-order kinetic model with high removal efficiency (∼95% within 5 h at pH 5.0). The adsorption isotherms were well fitted by Langmuir model, implying that U(VI) uptake on C@HAp/Arg was monolayer coverage. It was found that the maximum adsorption capacities of CSs, C@HAp and C@HAp/Arg toward U(VI) were calculated to be 23.16, 72.09 and 569.66 mg/g, respectively, at 298.15 K and pH 5.0, and thermodynamic parameters revealed that the adsorption processes of U(VI) were spontaneous and endothermic. In addition, effect of co-existed ions and CO 3 2− concentrations demonstrated that U(VI) adsorption on C@HAp/Arg was weakly interfered by foreign ions and carbonate concentrations. More importantly, the adsorption performance of U(VI) on C@HAp/Arg was still over ∼87% after five cycles. Therefore, it was noted that the versatile C@HAp/Arg could be potentially used as a powerful building block for the enrichment and disposal of U(VI) from aqueous solutions, which could efficiently reduce the potential toxicity of U(VI) in the U(VI)-contaminated water. [ABSTRACT FROM AUTHOR]

A novel low-cost, effective and environmental-friendly laminated carbon nitride decorated with polydopamine (PDA) and grafted with polyethyleneimine (PEI) brush ( l -C 3 N 4 /PDA/PEI 3 ) was successfully synthesized and applied as environmental cleaner for removing U(VI) ions from aqueous solutions under various environmental conditions. The adsorption isotherms fitted well by the Langmuir model, suggesting that the removal of U(VI) on l -C 3 N 4 /PDA/PEI 3 was monolayer coverage. The effects of different PEI contents were also investigated and the results demonstrated that the adsorption capacity of U(VI) on l -C 3 N 4 /PDA/PEI x decreased at higher content of PEI. Typically, various cations (Ca 2+ and Mg 2+ ) and SO 4 2− could inhibit the adsorption through competitive coordination with U(VI), while CO 3 2− promoted U(VI) sorption owing to the formation of indissolvable complexes. The main driving force between U(VI) and l -C 3 N 4 /PDA/PEI 3 was surface complexation with various functional groups (C C, C O, N C C, and C C or C H) and electrostatic attraction. According to the analysis of EXAFS spectra, the occurrence of U-C and U-U shell revealed that inner-sphere complexation and surface co-precipitation dominated the adsorption of U(VI) on l -C 3 N 4 /PDA/PEI 3 at pH 5.0. The composites were also applied to remove 243 Am(III), Cu(II) and Pb(II) ions at different pH values, and similar results were also found for these metal ions. Such a facile synthesis method and efficient removal performance suggested that the l -C 3 N 4 /PDA/PEI 3 materials might be a promising adsorbent for efficient elimination of radionuclides and heavy metal ions in environmental pollution management. [ABSTRACT FROM AUTHOR]

Hierarchical silicon dioxide-@-layered double hydroxide (SiO 2 @LDH) nanocomposites were synthesized by a facile in situ co-precipitation method, and characterized by XRD, FESEM, FT-IR and XPS in detail. The sorption of uranium (U(VI)) and methyl orange (MO) on SiO 2 @LDH were investigated as a function of pH, ionic strength, contact time and temperature. The results indicated that the sorption of U(VI) and MO were strongly dependent on pH, and weakly dependent on ionic strength, demonstrating that the interaction of U(VI) was mainly dominated by inner-sphere surface complexation and the sorption of MO was mainly attributed to electrostatic attraction due to the high removal efficiency (∼98% within 4 h for U(VI) ions, and ∼92% within 10 min for MO). The kinetics sorption of U(VI) and MO both followed the pseudo-second-order model well, suggesting that the sorption processes were chemical sorption. The sorption isotherms of U(VI) and MO on SiO 2 @LDH were well fitted by the Langmuir model, and the maximum sorption capacities of SiO 2 @LDH were calculated to be 303.1 mg·g −1 for U(VI) and 166.1 mg·g −1 for MO. The thermodynamic parameters revealed that the sorption of U(VI) and MO was spontaneous process. Integrating the experimental result analysis, the hierarchical SiO 2 @LDH may be a promising material for the efficient elimination of radionuclides and dyes from aqueous solutions in natural environmental pollution cleanup. [ABSTRACT FROM AUTHOR]

Radioactive uranium removal plays a key role in energy development and environmental security. Sulfide nanoscale zero-valent iron (S-NZVI) has good antioxidant capacity, dispersibility and activity to eliminate U(VI) from wastewater, but the removal efficiency is limited. To improve the reduction and adsorption capacity of S-NZVI, through treating Fe3+ solution by nitro-functionalized UiO-66 (UiO-66-NO 2) with high porosity, UiO-66-NO 2 enhanced S-NZVI adsorbent (S-NZVI/UiO-66) was prepared by liquid phase reduction method. The smaller size and larger specific surface area of S-NZVI/UiO-66 were confirmed by a variety of characterization techniques. Based on the excellent surface structure and reactivity, the U(VI) removal capacity of S-NZVI/UiO-66 (895 mg g−1) was much better than S-NZVI (434 mg g−1) and UiO-66-NO 2 (267 mg g−1). The impacts of pH, background ion strength, coexisting ions and different water environments on adsorption were studied via macroscopic batch experiments. The results showed that S-NZVI/UiO-66 could remove U(VI) adequately in a wide pH range. The removal rate was basically not affected by the concentration of NaNO 3 , demonstrating that the adsorption process of U(VI) on S-NZVI/UiO-66 tended to inner surface complexation. From XPS technique combined with the results of batch adsorption experiments, it was clear that the elimination mechanisms of U(VI) by S-NZVI/UiO-66 were mainly the physical adsorption, electrostatic attraction and complexation of UiO-66-NO 2 , and the reduction and complexation of S-NZVI. Therefore, it is believed that S-NZVI/UiO-66 has a great potential to be an excellent adsorbent in the field of the environment remediation. Moreover, S-NZVI/UiO-66 promises to be a novel nanomaterial for solving the problem of radionuclide contamination in practical environments. [Display omitted] • The pretreatment of UiO-66-NO 2 can effectively reduce the size of S-NZVI. • S-NZVI/UiO had a better specific surface area than the original S-NZVI. • The practical application potential of S-NZVI/UiO was confirmed. • The removal mechanisms were adsorption and reduction. [ABSTRACT FROM AUTHOR]

Electrical and electronic equipment (EEE) that greatly enhances global living standards has become indispensable in modern societies. In EEE, most electronic devices are protected by epoxy electronic packaging that exhibits outstanding mechanical property, high electrical resistivity and excellent solvent resistance. However, due to thermolability of electronic components and insolubility of epoxy, it is impossible to heal and recycle the packaged electronic devices non-destructively, resulting in a huge amount of e-waste during manufacturing and consumption. Herein, aromatic disulfide epoxy vitrimer packaged electronic devices were proposed, in which nondestructive healing and recycling were achieved. The epoxy vitrimer was prepared from aromatic disulfide-based epoxy and aliphatic amines at moderate temperature (≤100 °C), resulting in highly cross-linked networks, excellent solvent resistance and good thermal stability. The tensile strength was ∼71.9 MPa and the glass transition temperature was ∼115 °C. Moreover, it exhibited comparable electrical resistivity to reference epoxy, while lower dielectric constant was observed. In epoxy vitrimer packaged LED light, cracks could be readily healed at 150 °C through aromatic disulfide metathesis in networks, while the epoxy vitrimer exhibited topology freezing transition at ∼118 °C. Besides, relying on reactions between aromatic disulfide bonds and outer thiol groups, the epoxy vitrimer packaged LED light, printed circuit board and integrated circuit could be non-destructively recycled, while the epoxy vitrimer was degradable on demand. The aromatic disulfide epoxy vitrimer packaged electronic devices with nondestructive healing and recycling properties provide a better way to deal with substandard electric products and retired ones, leading to e-waste reducing, resource recycling and environment-friendly development in EEE. [Display omitted] • An aromatic disulfide epoxy vitrimer that reacted at moderate temperature was prepared to package electronic devices. • The epoxy vitrimer packaged electronic devices exhibited nondestructive crack-healing properties. • The epoxy vitrimer packaged LED light, printed circuit board and integrated circuit were non-destructively recycled. [ABSTRACT FROM AUTHOR]

[Display omitted] • TC-AO were used to adsorb U(VI) and Eu(III). • Abundant functional groups and good selectivity endowed TC-AO excellent property. • The practical application potential of TC-AO was confirmed. • The mechanisms were surface complexation and electrostatic interaction. Although two-dimensional transition metal carbides and carbonitrides (MXenes) are becoming increasingly popular in contaminant remediation field, the preparation of MXene nanosheets that can efficiently eliminate the target pollutants still deserves in-depth investigation. Here we produced amidoxime Ti 3 C 2 T x nanosheets (TC-AO), which were efficient radionuclide adsorbents with high stability and positive affinity, by introducing the amidoxime group into the Ti 3 C 2 T x MXene surface through grafting by diazonium salt. The high stability and abundant functional groups of TC-AO were demonstrated by different characterization techniques such as scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analyzer (TGA), and X-ray photoelectron spectroscopy (XPS). Multiple factors affecting the radionuclide removal performance were explored, including reaction time, temperature, pH, ionic strength, anions and cations. The experimental results demonstrated that the radionuclide uptake by TC-AO was a heat-absorbing, spontaneous single-molecule chemisorption process and was consistent with the pseudo-secondary and Langmuir models. When pH < 6, the mechanism of uranium removal was inner complexation, and as the pH continued to increase, uranium removal shifted to outer complexation. Furthermore, the results certificated that TC-AO exhibited fast reaction kinetics (reaching equilibrium in about 20 min), excellent removal efficiency (279.57 mg U·g−1 and 73.99 mg Eu·g−1), outstanding selectivity and good stability. The studies showed that TC-AO had good stability and functionality, which was not only valuable for the design of MXene based adsorbents, but also provided a meaningful option for the extraction of radioactive pollutants from wastewater. [ABSTRACT FROM AUTHOR]

Vitrimers, a new generation of polymeric materials, have been widely investigated to resolve the intersection of thermoplastics and thermosets, relying on the exchange reactions in networks. However, it is still a challenge to develop multi-functional vitrimer materials. Herein, multi-functional epoxy vitrimers that exhibited controllable dynamic properties, multiple-stimuli response, crack-healing and fracture-welding were prepared by introducing Fe 3 O 4 nanoparticles into the networks of dual dynamic epoxy vitrimers. It was revealed that the typical dynamic parameters of vitrimer including the characteristic relaxation time (τ), activation energy (E a), Arrhenius prefactor (τ 0) and topology freezing transition temperature (T v) could be readily adjusted in the multi-functional epoxy vitrimers. Moreover, the multi-functional epoxy vitrimers were simultaneously responsive to temperature, near infrared and magnetic field, while they could be driven by magnets, heated by near infrared and healed or welded by heating. Upon heating or near infrared, the cracks in samples could be successfully healed. Besides, by the cooperation of heating and magnet or near infrared and magnet, the multi-functional epoxy vitrimers were able to achieve non-touch welding of factures. These multi-functional epoxy vitrimers might have potential application in improving the reliability and extending the lifetime of polymeric materials. Meanwhile, the facile way to functionalize the epoxy vitrimers is estimated to be suitable for other vitrimer materials. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • SNZVI was synthesized and exhibited excellent affinity towards DCP. • Surface sulfidation enhanced the physicochemical properties of pristine NZVI. • The efficiencies of DCP by degradation were much higher than adsorptive processes. • Fenton-like reaction and generated ROS dominated the degradation processes of DCP. Surface sulfidation has become a desirable technique to enhance the physicochemical properties of nanoscale zero-valent iron (NZVI) and improve the decontamination efficiency for organic pollutants. However, the macroscopic elimination performance and microscopic reaction mechanism of sulfide NZVI (SNZVI) towards organic matters remains uncovered. Herein, we fabricated SNZVI via one-step dithionite-method and applied it for heterogeneous Fenton-like elimination of 2,4-Dichlorophenol (DCP). The sulfidation technique greatly improved the stability, specific area, oxidized resistance, hydrophobicity, and functionality. The efficiency of degradation (86.3%) was approximately 7 times higher than adsorption (12.6%) under N 2 condition, indicating the promising potential of SNZVI in environmental governance. Moreover, Fenton-like reaction and reactive oxygen species (ROS) were confirmed to dominate the degradation process, and the generated radicals had priority to degrade DCP rather than corroded SNZVI. Furthermore, the result of gas chromatography-mass spectrometry (GC–MS) confirmed that DCP was mainly decomposed into harmless alkanes and inorganic matters, which significantly reduced the perniciousness of DCP. Overall, this research bridged the knowledge gap between organic pollutant removal and the advanced oxidation reaction of NZVI-based materials after surface sulfidation. [ABSTRACT FROM AUTHOR]

Toxic metals and organic pollutants have become serious environment issues because these contaminants can cause indelible damage to human health and aquatic organism. Various materials have shown great potential in removing conventional contaminants and purifying water. Among them, carbon nanofibers (CNFs) have been regarded as promising candidates in the purification of water environments, owing to their distinct physical/chemical properties, but the connection between properties of CNFs and their removal performance receives few attentions. In this systematic review, we summarize the recent processes in synthetic strategies of CNFs, and highlight their water environmental applications via multiple interactions (π-π interaction, electrostatic interaction, and surface complexation). Some challenges and future outlooks of CNFs materials are briefly discussed. The content presented here will provide a helpful reference value for promoting the development of CNF-based nanomaterials and comprehend the significance of purifying water environments and protecting nature from pollutants. [Display omitted] • Abundant functional groups of carbon nanofibers promote water purification. • Surface modification and composite materials improve the removal performance. • Metal ions are removed via electrostatic interaction and surface complexation. • Organic contaminants are eliminated by π-π interaction and hydrophobic interaction. [ABSTRACT FROM AUTHOR]

Radioactive pollutants have always been the top priority in wastewater, and searching a green and efficient treatment technology remains a significant challenge. In this study, a novel melamine sponge supported sulfurized nanoscale zero-valent iron (MS@S-NZVI) material with high dispersion was firstly designed to effectively capture U(VI) from water environment. The target material could retain its original structure in water due to the excellent mechanical strength of MS, which greatly inhibited the aggregation of S-NZVI. A series of characterization techniques, such as SEM, XRD, FTIR, TGA and XPS, had proved the effective synthesis and excellent structural properties of the MS@S-NZVI. The faster reaction equilibrium (<1 h) and higher maximum adsorption capacity (180 mg/g at pH = 5 and 298 K) exposed the perfect performance of target material in the elimination of U(VI). In addition, further researches in different water systems exhibited that MS@S-NZVI had a significant U(VI) removal rate in simulated wastewater systems. Finally, the removal process of MS@S-NZVI to U(VI) could be divided into three pathways through the XPS technique, adsorption and reduction were the main reaction mechanisms. This study provides a new insight into the utilization of melamine sponge and a prospect for the practical application of S-NZVI in the removal of radionuclide. [Display omitted] • Melamine sponge was used to support S-NZVI for the first time. • The structure of sponge enabled MS@S-NZVI to disperse fully in water. • The practical application potential of MS@S-NZVI was confirmed. • Adsorption and reduction were the main reaction mechanisms. [ABSTRACT FROM AUTHOR]

In this paper, nanoscale zero-valent iron (NZVI), which has great potential in environmental purification is introduced. However, NZVI is easy to accumulate and oxidize, which limits its ability to remove pollutants. Hence several modified NZVI are proposed to overcome its shortcomings in this paper. The heavy metal ions, radionuclides and organic pollutants in the environment are removal by NZVI based materials, and their removal behaviors had been analyzed. This paper also reviews the factors affecting the removal of pollutants by NZVI-based materials, such as pH, ionic strength, contact time, reaction temperature, interfering ions and humic acids. In addition, it is also introduced that NZVI is toxic in the environment, and it also can be recovered and has different removal effects in different water environment. In short, this paper gives a comprehensive summary of NZVI, including its modification methods, pollutants removal, influencing factors of pollutants removal and implication to environment. It provides a strong theoretical basis for the future development of NZVI based materials. [Display omitted] • The characteristics of NZVI-based materials are briefly introduced and summarized. • The removal mechanisms of different pollutants are highlighted. • The influence factors and environmental implications are analyzed. • Future researches of NZVI-based materials in water remediation are discussed. [ABSTRACT FROM AUTHOR]

• The synthesis strategies of ZIFs are briefly introduced and summarized. • Batch experiment, spectral analysis and DFT are used to explore mechanisms. • The mechanisms mainly ascribe to coordination and electrostatic interaction. • Large SSA and sufficient functional groups endow ZIFs excellent performance. • Multi-factor influences demonstrate the practical application potential of ZIFs. With the rapid economic globalization and energy development, heavy metal ions/radionuclides are inevitably discharged into aqueous system and cause pollution, which seriously endanger human health and environmental sustainability. In recent years, zeolitic imidazolate frameworks (ZIFs) with huge specific surface area, excellent pore structure and abundant surface functional groups show great potential in the elimination of heavy metal ions/radionuclides. This review systematically summarizes the research progress of ZIFs and ZIF-based materials for capturing heavy metal ions/radionuclides. Firstly, the preparation and modification of ZIF-based materials are briefly introduced. Then, the removal behaviors and possible interaction mechanisms between ZIF-based materials and pollutants are explored through macro-batch experiments, micro-spectroscopy analyses and theoretical calculations. In addition, the partition coefficient as evaluation indicator was employed to objectively compare the removal performance of ZIFs and other commonly used traditional adsorbents for heavy metal ions/radionuclides. Finally, the challenges and prospects of ZIF materials in environmental governance are briefly discussed so as to provide references for future research and practical applications. [ABSTRACT FROM AUTHOR]

Highly porous zeolitic imidazolate frameworks (ZIFs), with disparate metal ions (ZIF-8 and ZIF-67), disparate organic ligands (ZIF-9 and ZIF-67), single or double central metal atoms (ZIF-8, Zn/Co-ZIF and ZIF-67) were prepared and used in the elimination of typical radionuclide U(VI). The detailed interaction mechanisms were studied by batch experiments, spectral analyses and DFT calculation. Langmuir isotherms model revealed a decreasing tendency to remove U(VI): ZIF-8 (540.4 mg/g) > Zn/Co-ZIF (527.5 mg/g) > ZIF-9 (448.6 mg/g) > ZIF-67 (368.2 mg/g). Based on the effects of pH and foreign ions, FTIR and XPS spectra analyses, the possible interaction mechanisms of U(VI) onto ZIFs were surface complexation and electrostatic interaction. Among them, ZIF-8 with Zn metal center and 2-methylimidazolate organic ligand had the best elimination capacity for U(VI) because of its large surface area, active metal ion and abundant nitrogen-containing groups (e.g., C–N, Zn–N and C N). Specially, the adsorption energy of ZIF-8-Zn2-UO 2 2+ structure was −2.299 eV obtained by DFT calculation, illustrating that U(VI) and N atoms were formed the most stable bidentate coordination compounds. This paper highlights the effects of the hydroxylated metals, the functional groups of the imidazole ring on the elimination of U(VI), which can provide constructive suggestions for further adsorbent materials amelioration. Image 1 • ZIF-8, ZIF-9, ZIF-67 and Zn/Co-ZIF were fabricated by stirring at room temperature. • Excellent structural performances endowed four ZIFs outstanding sorption capacity. • The differences in adsorption mechanism of four ZIFs were investigated in detail. • The N atoms of ZIF-8 formed bidentate coordination compounds with U(VI). [ABSTRACT FROM AUTHOR]

• Water stable Fe 3 O 4 @ZIF-8 was fabricated through a facile modification strategy. • Excellent structural performances endowed Fe 3 O 4 @ZIF-8 outstanding absorbability. • Multi-factors influence demonstrated the practical application potential. • The mechanisms were electrostatic attraction and inner-sphere surface complexation. • The excellent uptake capabilities made Fe 3 O 4 @ZIF-8 a promising adsorbent. The water stable core-shell microspheres (Fe 3 O 4 @ZIF-8) with strong magnetism were successfully fabricated through a facile modification strategy. Concrete procedures included firstly pretreatment of Fe 3 O 4 core with anionic polyelectrolyte to acquire negatively charged Fe 3 O 4 particle surface, followed by nucleation through attracting Zn2+ cation, and then growth of a thin layer of ZIF-8 (~25 nm). Various characterization techniques (SEM, TEM, FT-IR, XRD, VSM, BET and XPS) indicated that the Fe 3 O 4 @ZIF-8 microspheres were highly stable and magnetic with a large specific surface area (606.91 m2/g) and fairly sufficient functional groups (NH , OH, COOH, Zn O, N O and C N). Multi-factors affecting the radionuclides removal performance on Fe 3 O 4 @ZIF-8 was adequately explored, comprising contact time, temperature, pH, ionic strength, co-existing ions and extreme conditions. And the results showed that Fe 3 O 4 @ZIF-8 exhibited fast reaction kinetics (~30 min to achieve equilibrium), excellent uptake capabilities (539.7 mg U/g and 255.6 mg Eu/g), remarkable selectivity and favorable physicochemical stability. These researches suggested that Fe 3 O 4 @ZIF-8 could not only simultaneously achieve favorable stability and functionality, but also easily to be separated by external magnetic field after used in radioactive sewage treatment, which was of considerable practical utility in extracting radioactive wastes though in harsh circumstance. [ABSTRACT FROM AUTHOR]

• Core-shell Fe 3 O 4 @MoS 2 and MoS 2 @Fe 3 O 4 composites were synthesized. • Both Fe 3 O 4 @MoS 2 and MoS 2 @Fe 3 O 4 showed high removal capability for Cr(VI). • Both Fe 3 O 4 @MoS 2 and MoS 2 @Fe 3 O 4 are superparamagnetic. • Fe 3 O 4 @MoS 2 and MoS 2 @Fe 3 O 4 are eco-friendly during the synthesis process and wastewater treatment. • Synergetic reduction makes F@M an outstanding material for Cr(VI) removal. In this investigation, two novel magnetic core-shell Fe 3 O 4 @MoS 2 (F@M) and MoS 2 @Fe 3 O 4 (M@F) composites were synthesized and exploited for Cr(VI) elimination. Eco-friendly preparation methods were applied for the synthesis of Fe 3 O 4 and MoS 2 composites. The experimental results showed that both F@M and M@F have high saturation magnetization values (43.2 emu/g for F@M and 49.9 emu/g for M@F), excellent maximum sorption capacities of Cr(VI) at pH 5.0 and 298 K (324.3 mg/g for F@M, 290.2 mg/g for M@F), remarkable Cr(VI) removal efficiencies (Cr(VI) sorption equilibrium by both F@M and M@F can be reached in 90 min) and nice regeneration properties (the sorption capabilities of F@M and M@F decreased slightly after five consecutive sorption/desorption cycles). Chemical reduction of Cr(VI) to Cr(III) occurred on the surface of F@M and M@F, and the synergetic reduction of sulfur and ferrous ions made F@M an outstanding material for Cr(VI) removal. This paper highlights F@M and M@F as potential, eco-friendly and ultrahigh-efficiency materials for Cr(VI) pollution cleanup. [ABSTRACT FROM AUTHOR]

The surface tensions of 2‑diethylaminoethanol (DEAE)‑ N ‑(2‑aminoethyl)ethanolamine (AEEA), DEAE‑ N ‑methyl‑1,3‑propane‑diamine (MAPA) and DEAE‑1,4‑butanediamine (BDA) aqueous solutions have been measured by using the BZY-1 surface tension meter. The mass fractions of DEAE and AEEA/MAPA/BDA respectively ranged from 0.300 to 0.500 and 0.050 to 0.150. The temperature ranged from 303.2 K to 323.2 K. A thermodynamic equation was proposed to model the surface tension and the calculated results agreed well with the experiments. The effects of temperature and mass fraction of amines on the surface tension were demonstrated on the basis of experiments and calculations. The surface thermodynamics including surface enthalpy and surface entropy of blended amine aqueous solutions were also determined, and their temperature and mass fraction dependences were analyzed. • Surface tensions of DEAE and AEEA/MAPA/BDA aqueous solutions were measured. • Experiments were modeled satisfactorily by using a thermodynamic equation. • Surface thermodynamics including surface enthalpies and entropies were determined. • Effects of temperature and mass fraction on surface properties were illustrated. [ABSTRACT FROM AUTHOR]