Aluminum Ions Research Articles

Modified paddy husk carbon with linked fibrils of FeHO2 using aluminium as the surface regulator for enhanced As (III) removal in fixed bed system

Abstract The As (III) uptake capacity of Fe-impregnated AC greatly depends on the availability of active surface sites of iron oxide. In this context, utilizing aluminium as a surface regulator, we proposed a process to attach linked fibrils of FeHO2 to develop an adsorbent with enhanced As (III) adsorption capacity. The procedure was based on the hydrothermal process using paddy husk-based activated carbon, and both Iron and aluminium ions in the test hydrolysis solution. The exhaust time was observed to rise with increasing dose, falling flow rate, and influent concentration. The CCD optimization result showed that the FeAlPBC was an efficient and cost-effective adsorbent with a maximum response of 1681 min when the independent parameters were retained at 15.0 g FeAlPBC dose, 500 μg/L influent concentrations, 2.0 mL/min flow rate, and a desirability value of 0.986. The experimental results and Thomas and advection-diffusion models were in good agreement. The FeAlPBC samples can be recycled for four cycles with little to no reduction in adsorption capacity. Also, the TCLP test demonstrated that the used FeAlPBC were inert and could be put into landfills without risk. In conclusion, FeAlPBC is a strong contender for removing As (III) from potable water and has a wide range of potential future applications.

A dual functional turn off florescence sensor using metal–organic framework for sensitive detection of aluminum(III) in aqueous solution

AbstractAluminum, classified as one of the toxic heavy metals, has a recommended daily consumption limit of 3–10 mg, as specified by the World Health Organization (WHO). Herein, the selective and sensitive aluminum(III) fluorescence sensor based on TMU‐16 metal–organic frameworks (MOFs) in aqueous medium, is reported. A sensing pathway was found via the cation exchange between aluminum(III) and zinc(II) ions, and caused selectivity and sensitivity detection of aluminum(III) with a 5–100 ppm linear range and 1.99 ppm limit of detection (LOD).This sensor offers the advantage of accurately determining the concentration range of aluminum(III) ions. At low concentrations, only fluorescence quenching was observed, while at higher concentrations, fluorescence emission not only undergoes quenching but also exhibits a blue shift in wavelength. Notably, the sensor demonstrates no interference from cation solutions of mercury(II), zinc(II), nickel(II), lead(II), cobalt(II), cadmium(II), silver(I), chromium(III), and iron(III).Another significant feature of this sensor is its selectivity toward copper(II) and aluminum(III) ions, due to quenching fluorescence in the presence of copper(II) ion. The results presented the sensor's selectivity toward copper(II) at low concentrations and aluminum(III) at high concentrations.

Modification in structural, electrical and defect luminescence properties of ZnO nanorod films with Cu, Al and double-doping

Zinc oxide nanorods have broad application prospects in the field of photoelectric devices. However, the application as photodetectors in the visible light band is limited by their narrow luminescent spectrum and poor electrical conductivity. In this work, three different zinc oxide nanorod films respectively with Cu, Al and double-doping have been prepared for investigating the modifying effect of their defect luminescence and electric performance. In this paper, Cu doped zinc oxide with rod structure and Al doped zinc oxide with flaky structure are fabricated by hydrothermal method and sol-gel method, respectively. As for the double-doping, Al doped zinc oxide films are grown on the surface of Si by sol-gel method, and Cu doped zinc oxide nanorods are grown on the surface of Al doped zinc oxide films by hydrothermal method. The results show that the Cu doping can improve the number of defects, leading to the electrons transport from VZn to Zni and then releasing the photons. Alternatively, the trivalent aluminum ions exist in zinc oxide nanorods in the form of replacement or gap, increasing the carrier concentration, turn-on voltage and rectification ratio of zinc oxides. As for the Cu–Al double-doping, Al doped zinc oxide films are located between Cu doped zinc oxide nanorods and Si substrate and work as an intermediate layer of current. Trivalent aluminum ions can change the semiconductor properties of zinc oxide and make it have the performance of p-type semiconductor which can improve the electrical properties of zinc oxide semiconductor. Besides, the carrier concentration of Cu–Al double-doping zinc oxide is nearly 3 times higher than that of pure one. Increasing the carrier concentration can increase the current of ZnO–Si heterojunction in the dark, thus improving the photoelectric properties of ZnO nanorods.

Copper, Iron and Aluminium Electrochemical Corrosion Investigation during Electrolysis and Temperature Increasing

An experimental method to calculate average charge of metal ions by electrolysis at different temperatures is proposed. Aluminium undergoes dissolution to the Al3+ ions at all temperatures. Iron undergoes dissolution to the Fe2+ or the Fe3+ ions and copper undergoes dissolution to the Cu+ or the Cu2+. It depends on temperature and electric current density. Direct electric current value and anode mass decreasing were measured during electrolysis into concentrated NaCl solution in water (5 mol/kg or 23.1%, freezing point equals -22°C, pH 6.5–7.5) at room temperature and 100°C. The average charges of copper, iron, and aluminium ions were calculated using Faraday’s law of electrolysis at electric current density 3,000 A/m2 (or 30 A/dm2): +3 for aluminium; +2 for iron; and +1 for copper at room temperature, and +3 for aluminium; +2 for iron; and +1.5 for copper at temperature 100°C. The main condition was zAl=3. We concluded that calculations of the average metal ions charges, zFe and zCu, were correct since zAl=3. The result is as follows: the Al3+, the Fe2+, and the Cu+ ions dissolve into concentrated NaCl solution in water at room temperature; the Al3+, the Fe2+, the Cu+ and the Cu2+ ions (50%/50%) dissolve into the solution at temperature 100°C. We have obtained experimentally and by mathematical modelling that aluminium anodes (cylindrical or spherical) dissolve into the solution more rapidly with temperature increasing during electrolysis accordingly to the Arrhenius law, while copper anodes (cylindrical or spherical) dissolve more slowly with temperature increasing from room temperature to temperature 180°C like “inverse Arrhenius law”. Iron electrochemical corrosion rate practically does not depend on temperature below 100°C (and, obviously, up to 180°C) like “zeroth Arrhenius law”. The spherical anode effect is greater than the cylindrical anode effect in 1.5 times.

Physical-chemical study of the interactions of aluminum(III) ion with fine decomposed peat of Arroio Silva, Santa Catarina, Brazil

The interactions of the fine decomposed peat (FDP) of Arroio Silva, SC, Brazil, with the Al(III) ion were studied. The infrared (IR) spectrum confirmed the presence of the characteristic functional groups of peat. Kinetic studies revealed that, with a high correlation coefficient, the pseudo-second-order model shows a good agreement between the experimental and calculated qe values. This indicates that in the adsorption of Al(III) ion the determining step is a chemical adsorption, involving chelation. The process is described by the Langmuir adsorption model, which is limited to the formation of a monolayer of metallic ions. According to this model, the maximum adsorption capacities at pH 1.0, 2.5 and 4.0 were, respectively, 5.42, 5.89 and 6.09 ​mg of aluminum per gram of peat. The suggested adsorption mechanism involves the complexation of the Al(III) ion with the oxygenated groups present in the peat. The electron microscopy analysis showed a rough and porous surface and the determination of the point of zero charge (PZC) indicates that the interactions of the Al(III) ion with the peat are much stronger than simple electrostatic interactions. The molar amounts of the most important functional groups present and the equilibrium constants of Al(III) ion interactions with these groups were calculated and the distribution curves were obtained. At pH values up to pH ​= ​4.4, the Al(III) ion is preferably coordinated with the phthalic group. At higher pH values several interactions occur, for instance, between: a monohydroxide and the phthalic group, Al(OH)(Pht); a dihydroxide, a phthalic and a catechol group, which predominates at pH values of 4.5 to 8.2, [Al(OH)2(Pht)(Cat)]3-; and a monohydroxide bisphtalic, [Al(OH)(Pht)2]2-, a dihydroxide, a catechol and a salicylate group, [Al(OH)2(Cat)(Sal)]3-, which competes with the aluminate ion, Al(OH)4- . The linear relationship of Stern-Volmer suppression of the fluorescence of the aromatic groups present in the peat with the Al(III) ion confirms the equilibrium results.

Construction of cobalt hexacyanoferrate multivoid nanoframes as efficient aqueous aluminum ion batteries

In the search for innovative materials for aqueous Al-ion batteries, Prussian blue analogs (PBAs) have drawn significant attention due to their open-framework structures. Yet, PBAs face challenges like restricted capacity and rapid capacity deterioration, primarily stemming from the scarcity of redox sites and their inherent structural instability. In the current research, a synthesis of Fe–Co PBA multivoid nanoframe structures was achieved through straightforward co-precipitation techniques, aimed at optimizing Al-ion storage. Key to enhancing their performance was the modulation of the hydrothermal self-assembly reaction duration. As a result of this modulation, a morphological transition from nanocubes to multivoid nanoframes became evident, leading to the exposure of a higher number of active sites. This morphological transition also minimized the effects of volumetric shifts during the electrochemical charge/discharge cycles. Performance analysis indicated that the Fe–Co PBA multivoid nanoframes demonstrated a stable specific capacity, reaching 43 mAh g⁻¹ over 2000 cycles at 0.5 A g⁻¹ . Impressively, even under the more demanding current density of 1 A g⁻¹ , the specific capacity remained a substantial 36 mAh g⁻¹ after the same number of cycles. Comprehensive ex situ evaluations further underscored the predominant charge storage mechanisms, highlighting the reversible redox activities of the involved transition metals, coupled with the insertion/extraction dynamics of Al³ ⁺ ions.

Study of the synergy effect of high-intensity aluminum ions implantation into titanium and energy impact on the surface

The work studies the synergy effect of high-intensity implantation of aluminum ions and thesubsequent impact of a powerful pulsed ion beam on the microstructure and properties of titanium.Specimens of titanium were implanted for one hour at a temperature of 1170 K with an ion fluenceof 1021 ions/cm2. Layers with a thickness of about 150 μm were obtained. The energy impact wascarried out by a powerful nanosecond pulsed ion beam with an ion current density on the targetof 100 A/cm2. The paper presents data on changes in the elemental composition, surface morphology,and microstructure of ion-doped and energy-modified layers. It has been established that the additionalenergy impact on the ion-doped layer of a powerful pulsed beam improves microstructure at depthsgreater than 3.4 μm. The synergistic of high-intensity ion implantation of aluminum and the energyimpact of a pulsed ion beam improves the wear resistance of titanium by eighteen folds.

Tin oxide quantum dots embedded between graphene sheets to improve non-aqueous aluminum ion battery performance

A composite of tin oxide quantum dots (SnO2QDs) and reduced graphene oxide (RGO), was synthesized using the rapid microwave synthesis method and used as cathode material in the non-aqueous aluminum ion battery. In addition, graphene oxide (GO) and RGO were also prepared separately, and the properties of the resulting cathode materials were compared using XRD, FESEM, Raman, and HRTEM. RGO/SnO2QDs, GO, and RGO were mixed separately with a binder at a ratio of 90:10 and the resulting slurries were coated on a graphite sheet. The electrochemical performance of the graphite sheet, GO, RGO, and RGO/SnO2QDs cathodes was investigated using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and charge-discharge tests in an electrochemical cell containing an ionic liquid (AlCl3/Et3NHCl) as an electrolyte and aluminum as an anode. The battery with RGO/SnO2QDs cathode exhibited an excellent specific discharge capacity of 231 mAh g−1 at 2 A g−1 after 300 cycles with a Coulomb efficiency of 98.3 %. Furthermore, after 25,000 charge and discharge cycles at 2.5 A g−1, the Al||RGO/SnO2QDs battery demonstrated a specific discharge capacity of 163 mAh g−1, with a Coulombic efficiency of 89 %. Additionally, the superior battery also displayed impressive speed performance, achieving a specific discharge capacity of 124.6 mAh g−1 at 4 A g−1, with a Coulombic efficiency of 98.6 %. A comparison of the results of four prepared batteries showed that the synergistic effect of SnO2QDs and RGO layers makes for a suitable cathode material for rechargeable aluminum-ion batteries.

Naphthalene derived Schiff base as a reversible fluorogenic chemosensor for aluminium ions detection

Schiff base (HNPD) was achieved by reacting 2-hydroxy-1-naphthaldehyde with N-phenyl-o-phenylenediamine in enthanol medium. The spectroscopic analyses were done to establish the formation of Schiff base apparently. Further, synthesized Schiff base conjugate was successfully used as a fluorogenic chemosensor to detect aluminium ions (Al3+) with high fluorescence amplification among the other interfering various metal ions. The limit of detection of 0.0248 × 10−6 M and a binding constant of 6.19 × 103 M−1 were obtained by the receptor HNPD for Al3+ detection. A high influence of intramolecular charge transfer kinetics was established to realize the selective responsiveness towards Al3+ ions. Density functional theory approximation formulated the band energy modulation and localization and delocalization of electron density for the HNPD and Al3+ complexation. The developed sensor ultimately inspected on the real soil and water samples and ascertained the practical ability of Al3+ ions detection of HNPD chemosensor.

Research on reactivity evaluation and micro-mechanism of various solid waste powders for alkali-activated cementitious materials

Alkali-activated cementitious material (AACM) based on the utilization of solid waste is a new type of environmentally friendly inorganic material, which has the advantages of early strength, fast hardening, high strength, and better durability. The reactivity of solid waste powder is a key factor for its appropriate utilization in alkali-activated cementitious materials, necessitating a rational evaluation of its reactivity. The reactivity evaluation was conducted on various solid waste powders, including fly ash (FA), red mud (RM), recycled micro-powder (RMP), red brick powder (RBP), coal gangue powder (CGP), and cement kiln dust (CKD). The effects of NaOH concentration, weight ratio of water to solid waste powder (W/P) and curing humidity on the compressive strength were investigated，then the compressive strength under optimal conditions was determined based on response surface analysis. The compressive strength under optimal conditions was used to evaluate the reactivity of solid waste powders. Moreover, microscopic tests (e.g., XPS test, ICP test, and NMR test) were carried to evaluate the reactivity of the solid waste. The relative number of bridging oxygen (RBO) measured by the NMR method in conjunction with chemical composition analysis serves as an effective method for evaluating the reactivity of solid waste powders. The leaching rate of Silicon (Si) and Aluminum (Al) ions in the ICP method depended mainly on the NaOH concentration and the elemental content in the raw material. In addition, the binding energies of O1s, Si 2p, and Al 2p tested by the XPS method had no particular correlation with the compressive strength.

Aqueous aluminum-zinc hybrid ion batteries with urea-based hydrated eutectic electrolytes

Aqueous polyvalent ion batteries are more suitable for large-scale industrial applications than non-aqueous polyvalent ion batteries due to their intrinsic cost-effectiveness and eco-friendliness. Developing new electrolyte and finding compatible anode and cathode materials are key to improve battery performance and reversibility. Herein, we present a novel aluminum-urea hydrated eutectic electrolyte (AUHEE) by coupling Al2(SO4)3·18 H2O and urea. Urea-assisted hydrated aluminum ions weaken the strong interaction between aluminum ions and water molecules, thus inhibiting hydrogen precipitation and anode passivation by suppressing water dehydrogenation. Unique solvation structure of electrolyte enables the V2O5/AUHEE/Zn cell to exhibit high discharge capacity (250 mAh g−1) and long cycle life (1500 cycles), providing new insights into the development of aqueous polyvalent ion batteries with high performance.

Unlocking the Power of Multicatalytic Synergistic Transformation: toward Environmentally Adaptable Organohydrogel.

A sustainable and efficient multicatalytic chemical transformation approach is devised for the development of all-biobased environmentally adaptable polymers and gels with multifunctional properties. The catalytic system, utilizing Lignin aluminum nanoparticles (AlNPs)-aluminum ions (Al3+ ), synergistically combines multiple catalytic cycles to create robust, mechanically stable, and versatile organohydrogels. Single catalytic cycles alone fail to achieve desired results, highlighting the importance of cooperatively combining different cycles for successful outcomes. The transformation involves free radical crosslinking, reversible quinone-catechol reactions, and an autocatalytic mechanism, resulting in a dual crosslinking strategy that incorporates both covalent and ionic crosslinking. This approach creates a dynamic gel system with combined energy dissipation and storage mechanisms. The engineered organohydrogels demonstrate vital multifunctionalities such as good thermal stability, self-healing, and adhesive properties, flame-retardancy, mechanical resilience and durability, conductivity, viscoelastic properties, environmental adaptability, and resistance to extreme conditions such as freezing and drying. The developed catalytic technology and resulting gels hold significant potential for applications in flexible electronics, energy storage, actuators, and sensors.

The Role of Alanine in the Chemical Mechanical Polishing of Aluminum

With the evolution of integrated circuits, the transition from polycrystalline silicon to aluminum as the gate electrode has become prevalent due to its inherent advantages. This study considers the impacts of pH, H2O2 and alanine on the aluminum removal rate and surface roughness during chemical mechanical polishing (CMP) with abrasive colloidal silica. Alanine was incorporated as a complexing agent in the polishing slurry in an acidic environment. The mechanistic role of alanine in the aluminum CMP process was investigated with various techniques, including electrochemical tests, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and UV–visible spectroscopy (UV–vis). Additionally, density functional theory (DFT) calculations were used to examine the quantum chemical parameters of alanine and elucidate the complexation mechanism. The experimental results indicated that at an alanine concentration of 1.5 wt%, the Al removal rate was 2124.07 Å min−1 with a surface roughness of 1.33 nm. The interactions between alanine and the aluminum ions (Al3+) yielded soluble Al-alanine complexes, which facilitated corrosion on the Al and enhanced the removal rate.

Evolution of the Composition of the Ion-Alloyed Layer in a VT6 Titanium Alloy after Aluminum–Ion Irradiation

Evolution of the Composition of the Ion-Alloyed Layer in a VT6 Titanium Alloy after Aluminum–Ion Irradiation

Characterization, Structure, and Reactivity of Hydroxyl Groups on Metal-Oxide Cluster Nodes of Metal-Organic Frameworks: Structural Diversity and Keys to Reactivity and Catalysis.

Among the most stable metal-organic frameworks (MOFs) are those incorporating nodes that are metal oxide clusters with frames such as Zr6 O8 . This review is a summary of the structure, bonding, and reactivity of MOF node hydroxyl groups, emphasizing those bonded to nodes containing aluminum and zirconium ions. Hydroxyl groups are often present on these nodes, sometimes balancing the charges of the metal ions. They arise during MOF syntheses in aqueous media or in post-synthesis treatments. They are identified with infrared and 1 H nuclear magnetic resonance spectroscopies and characterized by their reactivities with polar compounds such as alcohols. Terminal OH, pairedµ2 -OH, and aqua groupson nodes are catalytic sites in numerous reactions. Relatively unreactive hydroxyl groups (such as isolatedµ2 -OH groups) may replace reactive groups and inhibit catalysis; some node hydroxyl groups (e.g.,µ3 -OH) are mere spectators in catalysis. There are similarities between MOF node hydroxyl groups and those on the surfaces of bulk metal oxides, zeolites, and enzymes, but the comparisons are mostly inexact, and much remains to be understood about MOF node hydroxyl group chemistry. It is posited that understanding and controlling this chemistry will lead to tailored MOFs and improved adsorbents and catalysts.

Microscopic mechanical properties of silicon nitride ceramics corroded in sulfuric acid solution

The microscopic mechanical properties including the bending strength and Young’s modulus for Si3N4 ceramics doped with Y2O3 and Al2O3 which was immersed in 5 wt% sulfuric acid solution using microcantilever beam specimens was investigated in comparison with the macroscopic results obtained in conventional three-point bending tests. Both the properties sharply dropped in very short periods of the corrosion in the microcantilever tests, resulting from the dissolutions of yttrium and aluminum ions of grain boundary glass networks, followed by the hydration. After the drops at the beginning of the corrosion, they showed little degradation afterwards. The degradation behaviors of the mechanical properties are basically the same as those in conventional macroscopic approaches; however, they changes appear in very short periods of the corrosion in the microcantilever bending tests. This study also verified that a small difference of a ratio of sintering additives results in different grain boundary strengths of Si3N4 ceramics.

Impact of dewatering inorganic coagulants on anaerobic digestion treating food waste leachate

Anaerobic digestion of food waste leachate (FWL) provides a viable solution for waste treatment and energy production. Returning solids from digested sludge to the reactor maintains a high microbial concentration and enhances digestion efficiency. However, this requires coagulants because the digestate has low dewaterability. This study analyzed methane production and microbial communities using biochemical methane potential tests for inorganic coagulants (AlCl3, Al2(SO4)3, FeCl3, and Fe2(SO4)3) in FWL treatment. Cumulative methane production was the highest in the control and decreased in the order of Fe2(SO4)3, AlCl3, FeCl3, and Al2(SO4)3. Iron ions inhibited H2S production while aluminum ions increased it compared to the control group. Despite the absence of significant changes in microbial communities following coagulant injection, a substantial increase in damaged cells was observed. These findings highlight the intricate repercussions of coagulant introduction in anaerobic digestion, emphasizing notable alterations in methane production dynamics and the integrity of microbial cells.

Removal of Aluminum from Synthetic Rare Earth Leach Solution by Selective Complexation and Turbidity Point Extraction

During the leaching process of ion-adsorbed rare earth ores, large amounts of non-rare earth impurities such as aluminum and iron will be generated. This study selected glutamic acid as a complex agent to selectively calculate aluminum ions; then, added non-ionic surfactants and extract and separate aluminum ions from a rare earth solution using the cloud point extraction method. The effects of solution pH, reaction temperature, equilibration time, amount of glutamic acid, reaction time, and amount of Triton X-114 on aluminum extraction were investigated. The results showed that with a Mglu:MAl ratio of 3:1, a solution pH of 4.5, a constant temperature of 40 °C, and the addition of 10 mL Triton X-114 after 10 min of reaction time, the single extraction efficiency of aluminum ions reached 78.01%, and the extraction efficiency of rare earths was only 5.09% after 10 min of equilibration time. The reaction equation of glutamic acid with aluminum ions was determined, and the lowest extraction concentration of aluminum ions in the glutamic acid complexation extraction solution was found to be cAl = 0.045 ± 0.003 g/L, with a separation coefficient of β(Al/RE) = 66.15. This result indicated that the aluminum ions in the mixed solution could be effectively separated from the rare earth ions when using glutamic acid as a complexing agent in combination with the turbidity point extraction method.

Effects of miR-204-5p and Target Gene EphB2 on Cognitive Impairment Induced by Aluminum Exposure in Rats.

Aluminum is a common environmental neurotoxin. Aluminum ions can cross the blood-brain barrier and accumulate in different brain regions, damage brain tissue, and cause cognitive impairment, but the molecular mechanism of aluminum neurotoxicity is not precise. This study investigated the effects of miR-204-5p, target gene EphB2, and downstream signaling pathway NMDAR-ERK-CREB-Arc on cognitive dysfunction induced by aluminum exposure. The results showed that the learning and memory of the rats were impaired in behavior. The accumulation of aluminum in the hippocampus resulted in the damage of nerve cell morphology in the CA1 region of the hippocampus. The expression level of miR-204-5p was increased, and the mRNA and protein expressions of EphB2, NMDAR2B, ERK1/2, CREB, and Arc were decreased. The results indicated that the mechanism of impaired learning and memory induced by aluminum exposure might promote the expression of miR-204-5P and further inhibit the expression of the target gene EphB2 and its downstream signaling pathway NMDAR-ERK-CREB-Arc.

Interactions between alkali-activated and cement-based mortars and biofilm and their influence on microbial induced mortar deterioration

Alkali-activated fly ash (AAF) and alkali-activated slag (AAS) mortars were exposed to the sewage environment with acidophilic sulfur oxidizing bacteria and high concentration H2S to study their interaction. It was found that when they suffered the biogenic sulfuric acid attack, both the AAF and calcium aluminate cement (CAC) mortars had a strong inhibition effect on the growth and activity of microorganisms. There are more aluminum ions dissolved from AAF mortar into sewage, and its structure was characterized by the increase in 100-1000 nm pores. Still, a hard high silicon skeleton was formed to keep the apparent intact. However, CAC mortar had a higher killing rate for the bacteria in the attached biofilm. For AAS mortar, the formation of excessive gypsum increased the macropores content and was more conducive to the growth of biofilm, thereby accelerating the penetration of corrosive medium and the deterioration of mortar.