Metal Research Articles

Enhancement of Anticancer Potential of Artemisinin Derivatives through N-glycosylation.

Cancer cells have significantly higher intracellular free-metal ions levels than normal cells, and it is well known that artemisinin (ART) molecules or its derivatives sensitize cancer cells when its endoperoxide moiety combines with metal ions, resulting in the production of reactive oxygen species, lysosomal degradation of ferritin, or regulation of system Gpx4 leading to apoptosis, ferroptosis or cuproptosis. Artemisinin derivatives (ADs) are reported to interfere more efficiently with metal-regulatory-proteins (MRPs) controlling iron/copper homeostasis by interacting with cytoplasmic unbound metal ions and thereby promoting the association of MRP to mRNA molecules carrying the respective sequences. However, the simple artemisinin analogues are required to be administered in higher doses with repeated administration due to low solubility and smaller plasma half-lives. To overcome these problems, amino ARTs were introduced which are found to be more stable, and later on, a series of ARTs derivatives containing sugar moiety was developed in search of analogues having good water solubility and high pharmacological activity. This review focuses on the preparation of N-glycosylated amino-ART analogues with their application against cancer. The intrinsic capability of glycosylated ART compounds is to give sugar-- containing substrates, which can bind with lectin galectin-8 receptors on the cancer cells making these compounds more specific in targeting cancer. Various AD mechanism of action against cancer is also explored with clinical trials to facilitate the synthesis of newer derivatives. In the future, the latest nano-techniques can be used to create formulations of such compounds to make them more target-specific in cancer.

Selective recovery of lithium from aqueous solution with hydrophobic deep eutectic solvent based on quantum chemical calculations and experimental investigation

Developing green and efficient extractants for selectively recovering lithium from salt lake brine is beneficial for alleviating the increasingly growing demand for lithium resources. This study developed a novel hydrophobic deep eutectic solvent (HDES) for selective recovery of Li+ from simulated salt lake brine solutions. Under the optimal experimental parameters, the single extraction efficiency of Li+ was 70.18%, β (Li+/ Na+) and β (Li+/Mg2+) were 22.32 and 947.58, respectively. Cycle experiments verified the high stability and good cycle performance of HDES. The conditions affecting the extraction efficiency of Li⁺ were optimized through experiments, and the high stability and good cyclic performance of HDES were verified. The extraction ability and mechanism of HDES for different metal ions were studied based on FTIR spectra combined with density functional theory. The calculation results showed that the order of extraction capacity of HDES for metal ions was: Li+>Na+>Mg2+. This calculation results were identical to the experimental results. This research will help develop HDES for the selective recovery of lithium from aqueous solutions containing high concentrations of Mg2+, helping to address the urgent global demand for lithium resources.

A Practical Guide to Metal Ions Dynamic Nuclear Polarization in Materials Science

In this protocol we outline the practical aspects and methodology for performing metal ions-based dynamic nuclear polarization (MI-DNP), focusing on materials science applications. In MI-DNP polarization is transferred from unpaired electrons of paramagnetic metal ions to nearby nuclear spins, thereby increasing the sensitivity of NMR spectroscopy. The protocol encompasses detailed steps for i) selecting suitable metal ions dopants based on chemical, structural and electron paramagnetic resonance (EPR) considerations, ii) characterizing the concentration, homogeneity and EPR properties of the dopant and iii) performing the MI-DNP experiment itself, including optimization of the field position and reliable assessment of the DNP enhancement factors. By adhering to this protocol, the interested reader can implement the MI-DNP approach in an efficient way, facilitating spectroscopic studies of functional materials.

In situ green synthesis of Rosa sterilis-based carbon dots for Fe3+ fluorescent sensing in baijiu

Baijiu is susceptible to contamination by Fe3+ during brewing and storage, and it is crucial to select a convenient method for the detection of Fe3+. In this work, we developed a one-step hydrothermal in situ green synthesis of blue fluorescent carbon dots (RS-CDs) from Rosa sterilis. A series of characterization of RS-CDs was carried out, and it was found that RS-CDs derived from biomass materials were environmentally friendly and low toxic, with an average particle size of 2.75 nm, a graphitic structure, and a surface rich in functional groups related to C, N, and O atoms. In addition, the PL of RS-CDs exhibited excitation-dependent behavior. The emission center was redshifted from 448 nm to 530 nm at excitation wavelengths ranging from 320 nm to 460 nm. After investigating the selectivity of RS-CDs for different metal ions, we found that RS-CDs had the highest quenching efficiency for Fe3+ and exhibited a static quenching mechanism. The LOD was 0.959 μM in the linear range of 0-140 μM. In addition, RS-CDs were successfully used for the detection of Fe3+ in four kinds of basic flavor baijiu, as well as in different containers for storage of baijiu. The study demonstrated that Rosa sterilis can be used to produce green and low-cost CDs, and the prepared RS-CDs can be conveniently, rapidly and selectively detected Fe3+ in the baijiu system, which is of potential application.

Preparation of cellulose nanofiber/polyvinyl alcohol-based composite films for metal ion detection by starch/disodium calcium ethylenediaminetetraacetate synergistic complexation effect

Heavy metal pollution causes irreversible damage to plants, animals, and humans. Therefore, it is meaningful to develop facile, fast, and efficient strategies for heavy metal ion (HMI) detection. Here, a portable composite film (CPSE) was designed for HMI detection with high sensitivity and wide detection range. The CPSE was prepared by using cellulose nanofibers (CNF)/polyvinyl alcohol (PVA) as the matrix and utilizing modified starch (HPS) to assist disodium calcium ethylenediaminetetraacetate (EDTA-Ca) to form stable complexes with HMI. The R, G and B values (the three primary colors of light) were captured using an image acquisition system to produce an HMI standard color card successfully. Specifically, the composite film can effectively distinguish Cu2+, Pb2+ and Fe3+. The response time of the composite film to HMI was 2–4 s, and the detection ranges of Cu2+ and Fe3+ were 5–700 ppm and 10–1000 ppm, respectively. Additionally, the synergistic effect of HPS and EDTA-Ca led to the increase in tensile strength (1.59–1.71 times), tear strength (3.29–3.57 times), and glass transition temperature (~ 6 °C) compared to CNF/PVA/HPS and CNF/PVA/EDTA-Ca films. This study confirms the value of CPSE films as materials for HMI detection and suggests innovative ideas for designing similar biomass detection materials in the future.

Synergistic Modification of Ti/PbO2 Electrodes with Metal Ions (Nd, Al, Bi) and STAB Surfactant for Electrocatalytic Treatment of Desulfurization Wastewater

In this study, PbO2 electrodes are modified by co-doping with different metallic elements (Nd, Al, Bi) and stearyl trimethyl ammonium bromide (STAB) using the electrodeposition method. The modified electrodes, designated as Ti/PbO2-Nd-STAB, Ti/PbO2-Al-STAB, and Ti/PbO2-Bi-STAB, are then applied in the electrochemical degradation of desulfurization wastewater. The surface morphology, crystal structure, and elemental valence of the prepared electrodes are analyzed using scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). Their electrochemical performance and stability are assessed by linear sweep voltammetry (LSV), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and accelerated life testing (ALT). The results reveal that modification with metallic elements and STAB significantly enhances the physicochemical and electrocatalytic performance of the Ti/PbO2 electrode. Among the modified electrodes, the Ti/PbO2-Nd-STAB electrode exhibits the most compact and homogeneous surface morphology, the highest oxygen evolution potential (OEP, 2.33V vs. SCE), the lowest chlorine evolution potential (CEP, 1.44V vs. SCE), the largest electrochemically active surface area, the lowest charge transfer resistance, the highest electrochemical stability, and a prolonged accelerated life (65h, which is 17h longer than that of the unmodified electrode). Further, the optimal electrochemical oxidation process parameters for desulfurization wastewater are determined as follows: current density = 50mA/cm2, temperature = 35 ℃, electrode spacing = 3.0cm, and stirring rate = 300rpm. After 300min of electrolysis, the Ti/PbO2-Nd-STAB electrode achieves a Cl− removal rate of 86.9% and a chemical oxygen demand (COD) removal rate of 71.2%. After 10 cycles, the Cl− and COD removal rates decrease by 2.8% and 1.8%, respectively. Besides, Tafel curve analysis indicates that the chlorine evolution reaction follows the Volmer-Tafel mechanism, with the recombination of adsorbed Cl− ions on the surface oxidation film being the rate-determining step. Overall, the Ti/PbO2-Nd-STAB anode exhibits immense application potential in the treatment of desulfurization wastewater.

Catalytic effect of the in-situ rhodium(III) complexes in surfactant medium on the auto-oxidation of 1,2-hydroxyphenylthiourea: A theoretical and experimental study for rhodium(III) sensing

1,2-hydroxyphenylthiourea(HPTU) undergoes auto-oxidation to form an yellow colored dimer. The process of auto-oxidation is enhanced by the presence of trace quantities of transition metal ions and transition metal complexes that act as catalysts. In the current study, catalytic potential of rhodium(III) complexes on the auto-oxidation of 1,2-hydroxyphenylthiourea(HPTU) was studied theoretically using quantum mechanical calculations and experiments were carried out using photometry and fluorometry. DFT studies inferred that [Rh(Py)6]Cl3 showed a better catalytic activity in the dimerization of HPTU. Theoretical studies were subsequently validated through experiments using photometric methods and the range of detection was determined to be 6 ng/mL–100 ng/mL. The detection limit was observed to be 2 ng/mL. Analytical parameters such as pH, reagent concentration, metal ion concentration, appropriate activators and surfactants were established.

Transforming waste into multifunctional nanomaterials: Mg-doped carbon dots from cow dung for Y(III) detection and biomedical applications

Rare earth metal Yttrium (Y3+) plays a vital role in many electronic devices however, discarding these devices eventually contaminates the environmental sources. Herein, we have developed a Mg-doped carbon dots (M-CDs) as a fluorescent probe for selective and sensitive determination of Y3+ in water bodies. The M-CDs having maximum emission at 420 nm upon 310 nm excitation with 20 % quantum yield and which was synthesized from upcycling of agricultural waste i.e., cow dung by simple carbonization followed by hydrothermal method. M-CDs were confirmed using different analytical and characterization techniques as well as stable in different pH and ionic strength solutions. The M-CDs was highly selective towards Y3+ ions over different metal ions with significant blue shift. This fluorescent probe performs a good linear relationship between the different concentrations of Y3+ ion and fluorescence intensity (R2 = 0.99) within the range of 0.2 to 20 μg/mL with a detection limit of 0.019 µg/mL. The study indicates quenching of Y3+ was result of dynamic quenching and the Inner Filter Effect (IFE) effect. Also, the cytotoxicity of M-CDs was checked via CAM assay and significant growth in blood vascularization with healthy growth of chick embryo confirmed the M-CDs were biocompatible. The nontoxic M-CDs was employed for MCF-7 breast cancer cell imaging which gives bright blue fluoresce under UV light excitation. Further, aiming to a circular economy approach the residual carbon remaining after hydrothermal was used as reactivated carbon for the abatement of environmental pollutants. The sustainable, cost-effective and agricultural waste-derived Mg-doped CDs have potential applications in analytical, environmental, forensic as well as biomedical fields.

A multifunctional coconut shell biochar modified by titanium dioxide for heavy metal removal in water/soil and tetracycline degradation

Heavy metals and tetracycline pollute the environment and endanger human health. This work prepared a multifunctional coconut shell biochar (Ti-XBC) through NaHCO3 activation and TiO2 modification. The modified coconut shell biochar was characterized by various methods. Ti-4BC exhibited excellent removal performance for heavy metals. The maximum adsorption capacity of Ti-4BC on Cd2+, Pb2+, Cr3+, and Cr6+ reached 104.2, 136.8, 101.2, 112.4 mg/g in water. The adsorption of Ti-4BC for four metal ions had a competitive effect in the binary metal system. It also reduced the mobility of four heavy metal ions in soil. Density functional theory (DFT) calculations were employed to explain the mechanism of heavy metal removal. Additionally, the degradation performance and mechanism of Ti-4BC towards tetracycline were investigated. The results indicated that the maximum degradation rate was 99.4%. Overall, this work developed a multifunctional material capable of both removing heavy metals and degrading antibiotics, addressing the issue of single-function in biochar. This provided a novel approach for tackling complex and diverse environmental pollution scenarios.

Advances in deep eutectic Solvent-Based synthesis of nanomaterials for environmental remediation

The application of eco-friendly deep eutectic solvents (DES) in the functionalization and synthesis of adsorbent materials has gained significant research interest in recent times. These materials, employed for treating polluted water primarily through degradation or adsorption, are emerging as sustainable alternatives to traditional technologies. However, the information regarding the functionalization and synthesis of adsorbent materials using DES is dispersed throughout the literature. This review aims to consolidate and clarify the extensive information available on the synthesis and functionalization of DES-based adsorbents, their application in water treatment as nanomaterials, and the future prospects of such technologies. DES presents an ideal alternative to conventional solvents for modifying and functionalizing adsorbents due to their lower toxicity, cost-effectiveness, and environmental friendliness. Most DESs effectively introduce desired functionalities and enhance the surface area of adsorbents, thereby greatly enhancing the removal of pollutants. This review compiles recent literature on the synthesis and modification of graphene oxides, carbon nanotubes, metal oxides, and other materials for the degradation/adsorption of pharmaceuticals, herbicides, dyes, pesticides, heavy metal ions, and other water contaminants. Besides this, DES-based nanomaterials have potential future applications in nanotechnology, nanofluids, nanocatalysts, biosensors, environmental remediation, among others. The anticipated exponential growth in these areas underscores the urgent need for such a review.

Physicochemical and processing properties and in vitro fecal fermentation characteristics of Prunus cerasifera Ehrhart polysaccharide

Prunus cerasifera Ehrhart fruit polysaccharide (PCP) was obtained after determining the optimal extraction conditions for complex enzyme-assisted hot buffer extraction based on single-factor experiments and response surface methodology, followed by characterization of its physicochemical, processing, rheological, and biological properties. PCP was a thermally stable carbohydrate with acidic functional groups and a molecular weight of 1398.69 kDa, exhibiting smooth, dense flake and honeycomb network microstructures. PCP had favorable hygroscopicity, moisturizing properties, water and oil-holding capacity, proemulsification capability, and in vitro antioxidant activity. The apparent viscosity of PCP in an aqueous system was dependent on concentration and temperature and was altered by the variety and amount of metal ions added; its aqueous solutions exhibited strong viscosity and hydrogel-forming tendencies at suitable concentrations, along with excellent hydrogel properties after gelation. Furthermore, PCP favored the growth of beneficial gut microbiota and associated microbes responsible for producing essential short-chain fatty acids. Overall, PCP displayed high potential as a multifunctional additive for applications in the food, pharmaceutical, and cosmetic industries.

A novel amidoxime-functionalized covalent organic framework adsorbent for efficient lead ion removal: synthesis and adsorption mechanism

Lead ions are highly toxic heavy metal ions and Pb(Ⅱ) in wastewater threatened seriously human health and environment. Therefore, an effective adsorbent must be developed to remove lead ions from wastewater. In this study, a polycrystalline amidoxime covalent organic framework (DBCC-NHOH) is synthesized by a post-modification method for the elimination of lead (II) from wastewater. The successful preparation of adsorbent (DBCC-NHOH) is demonstrated by the oxygen appearance in SEM-EDS pattern and conversion of -CN to C=N-O and C-N in the FT-IR pattern. DBCC-NHOH is a crystalline porous material and its pore size, specific surface area and pore volume are 3.419nm, 28.154 m2/g and 4.2ⅹ10-8 m3/g respectively. The optimum conditions for the adsorption of Pb(II) by DBCC-NHOH are temperature 298K, time 180min, and pH 5. The maximum adsorption of DBCC-NHOH was 221.37mg/g. Kinetic and thermodynamic investigations indicate that adsorption of Pb(II) by DBCC-NHOH is a monolayer chemisorption and exothermic process. Selectivity experiments indicate that DBCC-NHOH can adsorb Pb(II) efficiently and selectively in complex multi-ion systems. In addition, the adsorption percentage of DBCC-NHOH remained up to 83.20% after five adsorption-desorption experiments. The XPS and FT-IR analyses and DFT results indicated that DBCC-NHOH utilized amidoxime function group to realize the high efficiency of Pb(II) adsorption by electrostatic attraction and chelation.

Concurrent removal of Fe(II), Cu(II), and Zn(II) cations from acid mine drainage by an industrial solid waste - steel slag: Behaviors and mechanisms

Acid mine drainage (AMD) contamination poses a severe environmental threat and is a significant risk to human health. There is an urgent need to develop environmentally sustainable and technically viable solutions for water contamination caused by heavy metals. In this study, steel slag (SS) was used as a secondary resource to concurrently remove Fe(II), Cu(II), and Zn(II) from AMD. Because of the loose and porous structure, abundant functional groups, fast sedimentation velocity, and excellent solid-liquid separation, SS showed exceptional removal performance for heavy metal ions. The adsorption kinetic data of Fe(II), Cu(II), and Zn(II) showed good regression with the pseudo-second-order model. Besides, the adsorption of Fe(II) by SS conformed to the Freundlich model, whereas the adsorption of Cu(II) and Zn(II) followed the Langmuir model, with the maximum adsorption amounts of Cu(II) and Zn(II) being 170.69 and 155.98 mg/g. Furthermore, competitive adsorption was observed among Fe (II), Cu (II), and Zn (II) in a multi-component system, with the adsorption priority being Fe (II) > Cu (II) > Zn (II). The removal mechanism of Fe(II), Cu(II), and Zn(II) in AMD by SS mainly includes electrostatic attraction, chemical precipitation, and surface complexation. Interestingly, the leached concentrations of Fe(II), Cu(II), and Zn(II) from the spent slag after calcination were all within the detection limit of the Chinese emission standard, demonstrating excellent environmental stability. Theoretically, this renders it a viable candidate for use as an additive in construction materials. Meaningfully, the work offers a practical approach for energy-efficient and eco-friendly heavy metal ions adsorption, and the secondary utilization of SS also contributes to the sustainable development of the steel industry. It is beneficial to implement the development concepts of clean production and efficient utilization of industrial solid waste.

Electrochemically Mediated Amine Regeneration-CO2 mineralization: Mechanism and influencing factors

High energy consumption due to the thermal amine regeneration is one of the key issues hindering its large-scale applications. Amine regeneration by electrochemical is a promising technology, which can reduce energy consumption by up to 40% for amine regeneration. However, there are still some problems during the utilization and storage of captured CO2. In response to the current problems, this study introduces an innovative approach termed Electrochemically Mediated Amine Regeneration-CO2 Mineralization (EMAR-M), which innovatively synergizes in-situ regeneration of CO2-rich amine with CO2 mineralization through an electrochemical method. Electrochemical analysis was utilized to examine the anodic and cathodic reactions of EMAR-M, incorporating findings from XRD and CO32- concentration analysis, the reaction pathways and mechanisms of EMAR-M were elucidated. The results suggested that the reaction of EMAR-M followed the order of electrochemically mediated metal ion release, in-situ metal-amine coordination desorption, directed migration of CO32- and mineralization of CO2. The analysis of influence factors identified that the types of amines, electrolytes and metal electrodes significantly influence the EMAR-M. Compared with DEA and TEA, MEA has good CO2 absorption and electrochemical regeneration properties, which is advantageous for EMAR-M. Although electrolytes such as NaCl, Na2SO4, and KCl did not significantly affect the CO2 absorption of the amine absorbent, NaCl can promote the redox reaction at the metal electrode, which also favors EMAR-M. Cu electrodes also favor EMAR-M due to its swift cathodic/anodic reaction rates. Compared to other technologies, EMAR-M can reduce energy consumption by up to 58% for CCUS. The utilization of calcium-based solid wastes such as calcium carbide slag for synergistic CO2 mineralization can further reduce the operating costs of the technology as well as enable green applications of solid wastes.

PE/PP fibrous adsorbents with bifunctional groups of tertiary amine and phosphate prepared by electron beam induced co-grafting for heavy metal adsorption of both cationic and anionic forms in acidic conditions.

A novel fabric adsorbent having bifunctional groups of tertiary amine and phosphate was prepared by co-graft polymerization of 2-diethylaminoethyl methacrylate (NMA) and 2-hydroxyethyl methacrylate phosphate (PMA) onto a polyethylene/polypropylene nonwoven fabric (PE/PP NF) under low-energy electron beam acceleration. The process involved pre-irradiating the fabric and immersing it in the comonomer solution for grafting. The kinetics of radiation-induced graft polymerization at a total dose of 100 kGy was investigated. For pre-irradiation at 100 kGy, the optimum condition offering highest degree of grafting was at 12 wt% of NMA, 8 wt% of PMA and 4 h of reaction time. The adsorption of anions using hydrogen chromate (HCrO4−) or Cr(VI) and cations using lead (Pb(II)), cadmium (Cd(II)) and copper (Cu(II)) in aqueous solution was carried out. The results demonstrated that the bifunctional adsorbent was able to adsorb both heavy metal anionic and cationic ions from water. The co-grafted adsorbents with tertiary amine and phosphate were able to adsorb 85% Cr(VI) anion and 29% Pb(II) cations from mixed Cr(VI) and Pb(II) solution at pH 3.0 and 71% Pb(II), 13% Cd(II) and 31 % Cu(II) from mixed Pb(II), Cd(II) and Cu(II) solution at pH 5.0. The unique achievement of this study is its hypothesis that a bifunctional adsorbent can be prepared from radiation-induced graft polymerization of two different monomers onto NF, along with proof that the prepared bifunctional adsorbent can actually absorb both cationic or anionic heavy metals forms. Additionally, the adsorbent's preparation offers a rapid and straightforward one-step grafting technique. Therefore, the new bifunctional adsorbents can remove heavy metal ions in aqueous solution, either in the cation or anion form, thus offering highly promising applications in industrial wastewater treatment.

Simultaneous structure and surface engineering of metal-organic framework derived LiNi0.5-xFe2xMn1.5-xO4 cathode material for improving high voltage performance of lithium-ion batteries

This study presents a novel material synthesis approach utilizing a terephthalic acid-based metal-organic framework as a precursor and employing an ethanol-assisted hydrothermal treatment to produce high-performance Fe-doped LiNi0.5Mn1.5O4 (LNMO) cathode material. This strategy yields a well-crystallized spinel structure with uniformly distributed transition metal ions. Additionally, the appropriate quantity of Fe dopant can achieve the desired Mn3+/Mn4+ ratio, level of structural disordering, and crystal phase purity for Fe-doped LNMO. The synthesis process also aids in forming an amorphous Li2CO3 surface layer, approximately 1 nm thick, which protects the active material from excessive reaction with electrolyte. The typical Fe-doped LNMO cathode (S-05) exhibits superior performance compared to a commercialized LNMO counterpart. It delivers an initial discharge capacity of 135 mAh g-1 at 1 C with exceptional cycling stability over 500 cycles (capacity retention of 90%) under high voltage (5.0 V vs. Li+/Li). Furthermore, its rate capability significantly improves, with a capacity retention of 85% (5 C/0.2 C). This enhanced performance aligns with evidence of activated Ni2+/Ni3+/Ni4+ redox reactions and suppressed cathode electrolyte interphase resistance, leading to promoted Li+ diffusion. Moreover, it is found the cathode helps alleviate electrolyte degradation at high voltages by inhibiting the formation of singlet oxygen in the electrolyte.

Functionalization of cellulose by facile Dissolution-Regeneration in A novel CS2/DBU/DMSO solvent system for detection of metal ions and antibacterial

Functionalization of cellulose by facile Dissolution-Regeneration in A novel CS2/DBU/DMSO solvent system for detection of metal ions and antibacterial

Fixation behavior of oceanic manganese nodule-sodium alginate composite microspheres for heavy metal release during manganese nodule mining

Research on the environmental impact of deep-sea mining is crucial, particularly for fragile deep-sea ecosystems. This research focuses on the issue of heavy metal release during mining activities. Through simulation experiments, we investigated the release of Cu2+, Co2+, and Ni2+ from sediments under disturbance conditions and the fixation behavior during the deployment of ocean manganese nodule-sodium alginate composite microspheres (OMN@SA). The experimental results revealed that mining disturbances cause the release of 0.291% of Cu2+, 7.34% of Co2+, and 4.13% of Ni2+ from sediments into the water, primarily in the form of exchangeable metals. Compared with the bottom adsorption, OMN@SA has a faster adsorption rate in the slow settling process. The removal rates of Cu2+, Co2+ and Ni2+ reached 54.0%, 78.3% and 61.8% for 5 h adsorption, and the bottom adsorption removal rates reached 96.4%, 97.8% and 95.1% for 30 d adsorption, which has a good removal effect. In addition, OMN@SA can effectively block the diffusion of Cu2+, Co2+, and Ni2+ from interstitial water to overlying water, and reduce the influence of interstitial water on overlying water. SEM-EDS, FTIR, and XRD analyses revealed that OMN@SA adsorbs heavy metal ions through its abundant -OH groups and incorporates Cu2+, Co2+, and Ni2+ into the crystal lattices of vernadite and todorokite via substitution or intercalation. This study provides guidance for the remediation of heavy metal release from deep-sea mining using adsorption methods and demonstrates the promising application prospects of OMN@SA.

One-pot synthesis of foamable bio-resin: High solid content, low viscosity and rapid low-temperature curing

The increasing global concerns surrounding sustainable resource development and energy-efficient utilisation have positioned the functional utilisation of natural biomass materials as a critical research hotspot in materials science. This study aims to enhance the utilisation of lignocellulose, a highly promising and abundant renewable energy source, to replace petroleum-based materials with wood-based materials. To achieve this objective, the study employed techniques such as liquefaction degradation, molecular reconstruction and directional induction to synthesise wood-based resin through a one-pot process, using poplar powder. The resulting resin exhibited a solid content ranging from 65 % to 68 % and viscosity between 8000 and 4000 mPa·s. Compared with resin formulations lacking divalent metal ions, the resin containing these ions demonstrated an approximate reduction of 8°C in peak curing temperature and a 42.96 % decrease in curing time. These characteristics satisfy the requirements for foaming resins, including high solid content, low viscosity and rapid curing at low temperatures. Additionally, the impacts of resin rheology and thermosetting on the foam pore structure were analysed using principles of rheology and thermodynamics. The integrated manufacturing process of the resin resulted in zero waste or by-products, thereby enhancing efficiency, conserving energy and demonstrating promising market prospects.

In Situ Synthesis of Metal-Organic Frameworks on Sulfonated Cellulose Nanofibrils

The intrinsic fragility and inferior processibility of metal-organic frameworks (MOFs) particles often restrict their functional application despite their high surface area and porous structure. We investigated the feasibility of sulfonated cellulose nanofibrils (SCNF) as a biopolymer and template to hybridize MOFs. SCNF was synthesized through periodate oxidation followed by bisulfite sulfonation and characterized using solution-state NMR spectra. The sulfonate groups increased electronegativity and enhanced the dispersibility of the cellulose fibers. More importantly, the negatively charged sulfonates could be manipulated as anchors for metal ions to initiate the in situ growth of MOFs along the surface of cellulose fibers. We have achieved the synthesis of three types of SCNF/MOF hybrids, namely, SCNF/ZIF-8, SCNF/ZIF-67, and SCNF/HKUST-1. These hybrids can be formed as free-standing aerogels, exhibiting remarkably high surface areas and flexibility for applications. The assessment of the adsorptive efficiency of the SCNF/ZIF-8 hybrid indicates that the hybrid material exhibited a notably higher adsorption capacity for methylene blue versus the SCNF control. DFT computational calculation provides further insights into the underlying adsorption mechanisms, revealing that the sulfonates on the SCNF and the nitrogen atoms in the ZIF-8 ligands primarily contributed to the affinity for methylene blue. SCNF offers a versatile and robust biopolymer substrate for templating a wide array of MOFs with promising applications as adsorbents and beyond.