Al Ions Research Articles

Mechanistic Origin for High Structural Stability of Single Crystalline Nickel‐Rich Cathode Materials Via Al and Sm Co‐Doping

AbstractNickel‐rich layered oxides have attracted many attentions for their superior specific capacity and low cost, but they are subjected to fast structural degradation during cycling. Herein, the Al and Sm co‐doped LiNi0.83Co0.07Mn0.10O2 (SC‐NCM‐AS) single‐crystal is demonstrated to overcome their cycling instability issue, and its mechanistic origin for improved structural stability is investigated. It is found that soluble Al ions are homogenously incorporated in the LiNi0.83Co0.07Mn0.10O2 (SC‐NCM) lattice, while Sm ions tends to aggregate in the SC‐NCM outer surface layer. The Li/Ni cation disordering is greatly suppressed through the pillaring effect of stronger AlO bond in SC‐NCM single crystals. Sm‐concentrated outer surface layer can effectively prevent the dissolution of transition metals from SC‐NCM‐AS and inhibit undesirable side reactions induced by the organic electrolyte. This synergistic effect facilitates to suppress the formation of LiOH/Li2CO3 and oxygen vacancies, resulting in released the internal strain, decreased in‐plane transition metals migration and gliding, and eventually preventing formation of nanocracks in SC‐NCM‐AS single crystals upon cycling at high cut‐off voltage. Consequently, Al and Sm co‐doped SC‐NCM exhibits a high specific capacity of 222.4 mAh g−1 and remarkable cycling performance with a capacity retention of 91.1% for 100 cycles.

Boosted carbon resistance of ceria-hexaaluminate by in-situ formed CeFexAl1−xO3 as oxygen pool for chemical looping dry reforming of methane

High potential to carbon deposition over metallic Fe0 greatly limits the improvement of methane-to-syngas selectivity via chemical looping technology. Herein, we found that the in-situ formed CeFexAl1−xO3 over ceria-hexaaluminate as “oxygen pool” could greatly improve carbon resistance even with presence of Fe0. Formation of CeFexAl1−xO3 only proceeds in ceria-hexaaluminate composite while not occurs in CeO2-Fe2O3-Al2O3, which was probably originated from the strong interaction between CeO2 and the adjacent Fe and Al ions in BaFe3Al9O19 hexaaluminate structure. CeFexAl1−xO3 with outstanding oxygen ion conduction capacity was in close contact with metallic Fe0 exsoluted from Fe-hexaaluminate in a unique CeFexAl1−xO3/Fe0/hexaaluminate sandwich-like structure, which provided a convenient pathway for CeFexAl1−xO3 as “oxygen pool” to supply sufficient oxygen for in-time oxidation of carbon over adjacent Fe0. Consequently, the recycled ceria-hexaaluminate displayed both outstanding carbon resistance and high CH4 conversion (∼90%) with enhanced syngas yield that 105% and 72% higher than CeO2-Fe2O3-Al2O3 oxide and Fe-hexaaluminate, respectively.

Investigating the fouling potential of the metal‐silicate complex on membrane by response surface method (RSM)

AbstractBACKGROUNDTo optimize the filtration efficiency of membrane systems for chemical mechanical polishing (CMP) wastewater, the fouling potential of silica, aluminum‐silicate complex, and copper‐silicate complex was investigated by the response surface method.RESULTSThe mathematical models for three kinds of fouling were successfully developed based on the SDI0.1μm‐1atm and MFI0.1μm‐1atm to describe the fouling potential. These models indicate that the metal‐silicate complex fouling was severe at a neutral pH. Moreover, the models reveal that the effect of metal ions on fouling potential is significant. Compared with the feed solution conditions of 500 mg SiO2 /L and pH 7.5, when 1 and 5 mg Al3+/L are added, the MFI0.1μm‐1atm values increase by 109% and 156%, respectively. In addition, when 1 and 5 mg Cu2+/L are added, the MFI0.1μm‐1atm values increase by 210% and 313%, respectively.CONCLUSIONThe decrease in filtration efficiency was in the order of copper‐silicate complex > aluminum‐silicate complex > silica. Therefore, the fouling potential increased significantly when the influent contained trace metal ions (Al3+ or Cu2+) at a near‐neutral pH, demonstrating the importance of managing pH and metal ions in CMP wastewater for membrane systems. In addition, the MFI0.1μm‐1atm is more suitable than the SDI0.1μm‐1atm for evaluating fouling potential. The SDI0.1μm‐1atm has limited value and a narrow range for fouling potential measurement. In contrast, the MFI0.1μm‐1atm is more sensitive and has a more comprehensive detection range. © 2023 Society of Chemical Industry (SCI).

Nanomaterial Sensing Advantages: Electrochemical Behavior, Optimization and Performance of f-MWCNTs/CS/PB/AuE towards Aluminum Ions (Al3+) in Drinking Water

Modern technology has been evolving towards nanotechnology due to the materials that can be transformed and manipulated on micro and nanoscales. In terms of detection, nanomaterials offer substantial sensing advantages, particularly in terms of enhanced sensitivity, synergistic effect, stability and selectivity. The immobilization of nanoparticles could alter the physicochemical properties of the electrode’s surface depending on the type of materials synthesized and employed. This research examined the synthesis of multiwalled carbon nanotubes (MWCNTs) and chitosan (CS), as well as the immobilization of Prussian blue (PB) on the surface of a bare gold electrode (AuE). These materials have been reported to have strong electrical conductivity and nanomaterial compatibility. In contrast, aluminum has been described as a replacement for traditional water quality treatment processes, such as chlorination and ozonation. Aluminum concentrations must be monitored despite the use of chemical treatment for water quality. Hence, excessive levels of exposure frequently result in neurotoxic effects including Alzheimer’s and Parkinson’s disorders. In this experiment, the optimal conditions for f-MWCNTs, CS, PB, and AuE for the detection of Al3+ are phosphate-buffered saline (PBS) (0.1 M, pH 2) with 5 mM Prussian Blue; scan rate = 0.25 Vs−1; accumulation duration = 25 s; and volume = 10 mL (ratio of 4:6). The performance of f-MWCNTs, CS, PB, and AuE was measured between 0.2 and 1 ppm with a correlation coefficient of R2 = 0.9853 (y = 0.0387x + 0.0748). The limit of detection (LOD) of the modified electrode was determined to be 0.002 ppm, with a recovery of 98.66–99.56%. The application of nanoparticles resulted in various advantages, including high conductivity, a simple, less time-consuming preparation technique, and enhanced sensitivity and stability for detecting the lowest concentration of Al3+ in drinking water.

Superhydrophilic All‐pH‐Adaptable Redox Conjugated Porous Polymers as Universal and Ultrarobust Ion Hosts for Diverse Energy Storage with Chemical Self‐Chargeability

AbstractHerein, a new fibrous conjugated microporous polymer bearing phenazine species (PNZ‐CMP) is reported as a universal and ultrastable electrode to host various mono‐ and multi‐valent charge carriers for diverse aqueous rechargeable cells combining rapid kinetics, ultralong lifespan, and chemical rechargeability. The porous cross‐linked structure, interconnected donor‐acceptor network, and readily accessible active sites endow PNZ‐CMP with highly‐reversible redox activity, superhydrophilicity, facile electron transport, high ion diffusion coefficient, and all‐pH‐adaptability (−1 to 15) in aqueous electrolytes. Thus, adopting PNZ‐CMP electrodes enables good compatibility with H+/Li+/Na+/K+/Zn2+/Al3+ ions and fast surface‐controlled redox reactions for diverse aqueous battery chemistry. Multiple PNZ‐CMP‐based full cells show superior electrochemical performance especially ultralong lifespan, e.g., ≈84% capacity retention over 200 days for K+, ≈100% over 127 days for Zn2+, and ≈76% over 47 days for anion‐coordinated Al ions, surpassing small molecule counterparts and most previously‐reported corresponding systems. The spontaneous redox chemistry of reduced phenazine species with O2 is first explored to render PNZ‐CMP with repeatable chemical self‐chargeability in four electrolytes. Especially in 0.05 m H2SO4, an accumulative discharge capacity up to 48505 mAh g−1 is achieved via facile self‐charging, which can originate from the “reactive antiaromaticity to stable aromaticity” conversion of the redox moieties as revealed by theoretical studies.

Screen-printed water-in-salt Al ion battery for wearable electronics

Metal ion batteries with “water-in-salt” electrolyte are well known for their low cost and high safety, which are especially suitable for powering wearable electronics. Among them, the Al ion battery holds a great advantage in metal abundance and energy density, which has also been proved reliable with the “water-in-salt” electrolyte system. To facilitate its efficient manufacturing, screen-printing is adopted to develop a “water-in-salt” Al ion battery for the first time. Both the Al anode ink and the graphite cathode ink are prepared and printed onto opposite sides of a cellulose paper, while the “water-in-salt” AlCl3 electrolyte is stored inside the paper by an absorption-evaporation process. Specifically, three anode printing configurations are compared, whose effect on battery performance and durability is studied comprehensively. In general, the battery prototype can sustain a high specific current of 1.0 A g−1 and specific capacity of 120 mAh g−1. A satisfactory lifetime of 550 cycles is also achievable at a lower specific current of 0.25 A g−1. Moreover, this battery can tolerate repetitive bending of 1000 times and even the puncture of its electrodes, proving its great flexibility, robustness and safety for wearable applications. The monolithic battery pack printing is also demonstrated successfully in the end.

Molecular dynamics simulations of cascade events in AlN

The radiation tolerance and the ability to retain its piezoelectric response make aluminum nitride (AlN) a good candidate for emerging sensing technologies in nuclear reactor environments. Furthermore, it has been shown that doping the ceramic with additional metals can further improve the piezoelectric response. Fundamental understanding of the response of AlN to radiation is important for ultimately improving the material's properties. In this paper, we use molecular dynamics and a recently developed interatomic potential fitted to defect energies to investigate low energy collision cascades in AlN. We additionally investigate the electronic stopping effect in the damage production for 20 keV Al ions. Our results show that for all energies the number of Al surviving defects is larger than that of N defects. Additionally, we find that even though the ballistic energy loss is the dominating mechanism, it is important to take into account the electronic stopping in order not to overestimate the number of defects.

Spectrophotometric and Smartphone-based Dual Monitoring Method for the Determination of Al(III) Ions Using Fermented Black Carrot Juice (Şalgam/Shalgam) as a Green Chromogenic Agent

In this study, anthocyanin-rich fermented black carrot juice (şalgam/shalgam) was used as a chromogenic agent in order to develop eco-friendly, low-cost, simple, fast, and practical both visible spectrophotometric and smartphone-based methods for the determination of Al(III) ions in water samples. Formation of Al(III)-anthocyanin complex results in a color change from red to purple in direct proportion to the increasing Al(III) concentration. For the spectrophotometric analysis, the analytical response of the developed method between absorbance and logarithm of Al(III) concentration exhibits a satisfying wide linear concentration range from 37.0 to 1850.0 µM. The LOD and LOQ values are 6.67 µM and 22.0 µM, respectively. For smartphone-based analysis, the analytical response of the developed method between B values and Al(III) concentration obtained a linear concentration range from 18.5 to 111.0 µM. The LOD and LOQ values are 4.40 µM and 14.5 µM, respectively. LOD values are below the acceptable limit of Al(III) in water according to WHO (7.41 µM) for both methods. The interfering effect of common water ions was investigated, and the observed interferences from Sn2+, Fe2+, and Fe3+ were easily eliminated using enough concentration of Na2EDTA without affecting the blank absorbance/B value of the Al(III)−anthocyanin complex for two monitoring methods. The selectivity of the developed method was investigated in the presence of possible species such as benzoic acid, lactic acid, amino acids, and salt. Developed spectrophotometric and smartphone-based methods applied to real water samples and validated against the reference ICP-OES method at 95% confidence level using Student’s t- and F-tests.

Type-wide biochars loaded with Mg/Al layered double hydroxide as adsorbent for phosphate and mixed heavy metal ions in water

This study discussed the adsorption of mixed heavy metal ions (Cu2+, Co2+, Pb2+) and phosphate ions by ten pristine biochars and those with precipitated Mg/Al layered double hydroxide (LDH). The pristine biochars have adsorption capacities of 6.9–13.4 mg/g for Cu2+, 1.1−9.7 mg/g for Co2+, 7.8−20.7 mg/g for Pb2+, and 0.8−4.9 mg/g for PO43−. The LDH-biochars have markedly increased adsorption capacities of 20.4–25.8 mg/g for Cu2+, 8.6−15.0 mg/g for Co2+, 26.5−40.4 mg/g for Pb2+ with mixed metal ions, and 13.0−21.8 mg/g for PO43−. Part of the Mg ions but Al ions are released from the LDH-biochars during adsorption, counting less than 7.2% of the adsorbed ions. The pristine biochars have specific adsorption sites for Cu2+ and Co2+, separate Pb2+ sites related to ether groups on biochar, and areal-dependent sites for PO43−. There is no universal adsorption mechanism corresponding to mixed metal ion adsorption for individual pristine biochar involving different contributions of C–O–C, C–O–H, and CO groups and graphitic-N, pyrrolic-N, and pyridine-N groups. The LDH complexes with hydroxyl and carbonyl groups of biochar, and the LDH interacts with biochar's ether groups, which contributes to metal adsorption, against the conception that the biochar is merely a carrier of LDH as adsorbents.

CO2 methanation over Ni/Al2O3-ZrO2 catalysts: Optimizing metal-oxide interfaces by calcinating-induced phase transformation of support

A new strategy to prepare the NiO/Al2O3-ZrO2 catalyst with various interfacial structures by inducing different phase transitions of Al2O3 and ZrO2 via varying the precursor calcination temperature was proposed, and their CO2 methanation performance was subsequently investigated. The characterization of the catalyst showed that Ni was prone to bonding with Al ion during the calcination process and forming NiAl2O4 or strong interaction between Al2O3 and NiO. The reduced metallic nickel (Ni0) and partially unreduced NiAl2O4 exist in the state of Ni-NiAl2O4/Al2O3-ZrO2, forming a multi-interface system of Ni-O-Al, Al-O-Zr, and Ni-O-Zr. Moreover, this supplies medium-strength adsorption sites that play a key role in CO2 activation. The in-situ diffuse reflectance infrared Fourier transform spectroscopy (in-situ DRIFTS) analysis and catalytic activity revealed that the CO2 methanation was completed in a two-step coupling route of Reverse Water Gas Shift (RWGS) and CO methanation. The abundant interfaces of the catalyst effectively suppressed the sintering of Ni.

Structure and magnetic properties of Al3+ substituted M-type SrLaCo hexaferrite

M-type hexagonal ferrites (SrFe12O19) have attracted much attention as a widely used permanent magnet. Many studies have been done to improve permanent magnetic properties. In particular, the formula of La–Co co-replaced Sr–Fe has achieved higher performance. However, no one has studied the influence of a small amount of Al ions on the above formula. In this study, the Al3+ ion substituted M-type Sr0.7La0.3Fe11.75ￚxAlxCo0.25O19 (0 ​≤ ​x ​≤ ​0.12) hexagonal ferrites were synthesized by solid state reaction. The crystalline structure was investigated by using X-ray diffraction (XRD) and the Rietveld refining method. The morphological of powder and magnetically oriented bulk were observed by scanning electron microscopy (SEM), and magnetic properties were measured by physical property measurement system-vibrating sample magnetometer (PPMS-VSM) techniques. The results show that a single M-type strontium ferrite was obtained with the Aluminum (Al) content (x) from 0 to 0.08, and the impure phase appeared when x was 0.12. The lattice parameters a and c both decreased with the increasing Al3+ content. SEM images indicate the hexagonal platelet-like particles and the size of the magnetic powders about 2–5 ​μm, and the powders are easily arranged in one direction under a magnetic field. The saturation magnetization (Ms) of the hexaferrite decreased with the increase of x from 0 to 0.12, but coercivity (Hc) of the magnetic powders increased with Al3+ content (x) from 0 to 0.12.

Effect of Metal Ions on the Interaction of Condensed Tannins with Protein

A quantitative analysis of the precipitate effects of metal ions (Al3+, Fe2+, Cu2+, Zn2+) by bovine serum albumin (BSA) on two condensed tannins (CT) from sorghum and plum was presented in this study. The results showed that adding metal ions enhanced the precipitation of proteins by CT, depending on the type and concentration of the metal ions used in the reaction system. The presence of metal ions and precipitation results on the CT-protein complex showed that Al3+ and Fe2+ had a higher binding ability with CT and a weaker influence on the precipitation of the CT-protein complex than Cu2+ and Zn2+. However, when the initial reaction solution contained excessive amounts of BSA, the extra addition of metal ions had no significant effect on the amount of BSA precipitation. Reversely, adding Cu2+ or Zn2+ into the reaction solution increased the amount of precipitated BSA when the amount of CT was excessive. In addition, the amounts of CT from plum, rather than sorghum, generated more protein precipitate in the presence of Cu2+ or Zn2+, which may be due to the different binding modes between the metal ion and the CT-BSA complex. This study also proposed a model of the interaction between the metal ion and the CT-protein precipitate.

Role of delphinidin-3-glucoside in the sepal blue color change among Hydrangea macrophylla cultivars

The sepals of Hydrangea macrophylla (H. macrophylla) are famous for their color changes under different cultivation conditions. Despite the structure of the blue complex in blue sepals has been confirmed by chemical and biological studies on hydrangea, the mechanism of sepal color change is still not completely understood. In fact, not all cultivars with pink–red sepal color have blue sepals in acidic soils with Al ions. To determine the key factors affecting the bluing capability of sepal color in H. macrophylla, nine cultivars with different bluing capability of sepal color were tested to investigate the effect of the contents of aluminum, copigments and anthocyanins in sepals on the change in sepal color in this research. The results showed that delphinidin-3-glucoside directly determines the content of the blue complexes in sepals. Moreover, the proportion of delphinidin-3-glucoside among all anthocyanins in sepals was a key factor determining the bluing capability of sepal color in H. macrophylla. Based on the further research, it was concluded that the bluing capability of sepal color was positively correlated with the proportion of delphinidin-3-glucoside among all the anthocyanins in sepals, which was positively regulated by the transcription ratio of F3’5’H to F3’H in all the tested cultivars. This study provides useful data for cultivation, breeding, and further research on the molecular mechanism of the bluing capability of sepal color in H. macrophylla.

Al and Cr ions co-doped spinel manganese lithium ion-sieve with enhanced Li+ adsorption performance and structural stability

The Li1.6Mn1.6O4 driven lithium ion-sieve (LIS) is considered as a potential adsorbents for recovering Li+ ions from brines owing to their good theoretical adsorption performance and excellent adsorption selectivity. However, the poor cycle stability and the decrease of adsorption capacity resulting from the manganese dissolution loss limit its practical applications. In this work, to mitigate this issue, several novel Al and Cr co-doped manganese LISs were prepared by a facile hydrothermal synthesis method, followed by the acid treatment. The characterization results show that Al and Cr ions are uniformly doped into the spinel crystal structure of LIS, and the introduction of Al and Cr ions can cause the crystal shrinkage, decrease the Mn3+ content, and raise the mean valence of manganese in the co-doped samples, effectively improving their structural stability. Compared with un-doped ion-sieve H1.6Mn1.6O4, the optimal co-doped ion-sieve H1.6Mn1.54Al0.02Cr0.04O4 with 2% Al doping and 4% Cr doping possesses a higher lithium adsorption capacity, lower manganese dissolution loss, and stronger cyclic stability. Additionally, the H1.6Mn1.54Al0.02Cr0.04O4 possesses a high adsorption selectivity of Li + over Mg2+, Ca2+, K+ and Na+. Furthermore, the lithium adsorption is determined to be a chemical and monolayer adsorption process on the prepared LIS. The good lithium adsorption capacity and adsorption selectivity as well as the good recyclability make the prepared Al and Cr co-doped LIS a promising adsorbent for the efficient lithium recovery form brines.

Study on the flame retardancy of carrageenan fiber papers

Abstract Carrageenan fibers crosslinked with trivalent metal ions (Al3+ or Fe3+) were prepared into carrageenan fiber paper (Al/CAP, Fe/CAP) by the Rapid Kothen method, and their flame-retardant mechanism and flame retardancy were studied through LOI, VF, SEM, CONE, and TGA testing. The results showed that Al/CAP exhibited good flame retardancy and thermal stability, and its LOI value reached 52%. Meanwhile, the afterflame time and afterglow time of Al/CAP were 0 and 1 s, respectively, which indicated that it was not ignited and almost had no smoldering phenomenon. The flame-retardant performance of Fe/CAP is inferior to that of Al/CAP, with LOI of 32, but the total smoke emission (TSP) of Fe/CAP is lower in cone calorimetry test. Thus, CAPs (especially Al/CAP) can be widely used in the flame-retardant paper industry, due to their flame retardancy and environmental protection.

Electrochemical Deoxygenation of Alcohols into Alkanes

AbstractA direct electrochemical reductive approach for deoxygenation of alcohols has been developed in the presence of substoichiometric amount of AlCl3. The released Al ions from the sacrificial Al anode could combine with the chloride anion to regenerate the Lewis acid.

Water-Stabilized Vanadyl Phosphate Monohydrate Ultrathin Nanosheets toward High Voltage Al-Ion Batteries.

Al ion batteries (AIBs) are attracting considerable attention owing to high volumetric capacity, low cost, and high safety. However, the strong electrostatic interaction between Al3+ and host lattice leads to discontented cycling life and inferior rate capability. Herein, a new strategy of employing water molecules contained VOPO4 ·H2 O to boost Al3+ migration via the charge shielding effect of water is reported. It is revealed that VOPO4 ·H2 O with water lubrication effect and smaller steric hindrance owns high capacity and fast Al3+ diffusion, while the loss of unstable water upon cycling leads to a rapid performance degradation. To address this problem, ultrathin VOPO4 ·H2 O@MXene nanosheets are fabricated via the formed TiOV bond between VOPO4 ·H2 O and MXene. The MXene aided exfoliation results in enhanced VOwater bond strength between H2 O and VOPO4 that endows the obtained composite with strong water holding ability, contributing to the extraordinary cycling stability. Consequently, the VOPO4 ·H2 O@MXene delivers a high discharge potential of 1.8V and maintains discharge capacities of 410 and 374.8 mAh g-1 after 420 and 2000 cycles at the current densities of 0.5 and 1.0 A g-1 , respectively. This work provides a new understanding of water-contained AIBs cathodes and vital guidance for developing high-performance AIBs.

Al2O3 triggered in-situ crystallization of Gd3Al2Ga3O12 in glass and enhancement in magnetic and Faraday rotating properties

Nanocrystals doped transparent glasses or glass ceramics have shown promising tunable magnetic and magneto-optical performance. In this study, the Al2O3-induced in-situ crystallization of Gd3Al2Ga3O12 in tellurite glass was reported. 10–20 nm-cubic Gd3Al2Ga3O12 (Ia3d space group) nanocrystals formed in tellurite glass with Al2O3 content ≤ 0.75 mol% by 400 °C-heat treatment. When Al2O3 content in glass was higher than 0.75 mol%, excessive Al2O3 triggered the crystallization of orthorhombic GdAlO3 (Pnma) in which the Gd and Al ions existed as octahedral GdO8 and AlO6 units at a temperature higher than 398 °C. The in-situ crystallization influenced the glass network structure, broke the linkage of tetrahedral TeO4, and BO4, and formed trigonal pyramids TeO3 and BO3 instead. At the same time, nuclear magnetic resonance spectra revealed the conversion of AlO4→ AlO6, GaO4→ GaO6, and the changes from bridging oxygen to non-bridging oxygen as well. From energy-dispersive X-Ray analysis, Gd3+ clusters were observed, leading to the ferromagnetism of glass. Electron paramagnetic resonance spectra witnessed an enhancement of the Zeeman effect which is the reason for the improvement of Faraday rotation. Tellurite glass with 0.75 mol% Al2O3 after 400 °C-annealing (A75) showed a giant Verdet constant of 93 rad/T.m at 633 nm which is superior to most of the values from the literature.

Computational assessment of the impact of Cu(II) and Al(III) on β-amyloid42 fibrils: Binding sites, structural stability, and possible physiological implications.

One of Alzheimer's disease major hallmarks is the aggregation of β-amyloid peptide, a process in which metal ions play an important role. In the present work, an integrative computational study has been performed to identify the metal-binding regions and determine the conformational impact of Cu(II) and Al(III) ion binding to the β-amyloid (Aβ42) fibrillary structure. Through classical and Gaussian accelerated molecular dynamics, it has been observed that the metal-free fiber shows a hinge fan-like motion of the S-shaped structure, maintaining the general conformation. Upon metal coordination, distinctive patterns are observed depending on the metal. Cu(II) binds to the flexible N-terminal region and induces structural changes that could ultimately disrupt the fibrillary structure. In contrast, Al(III) binding takes place with the residues Glu22 and Asp23, and its binding reinforces the core stability of the system. These results give clues on the molecular impact of the interaction of metal ions with the aggregates and sustain their non-innocent roles in the evolution of the illness.

Reversible aqueous aluminum metal batteries enabled by a water-in-salt electrolyte

Aluminum (Al), the most abundant metallic element on the earth crust, has been reckoned as a promising battery material for its the highest theoretical volume capacity (8046 mAh cm−3). Being rechargeable in ionic liquid electrolytes, however, the Al anode and battery case suffer from corrosion. On the other hand, Al is irreversible in aqueous electrolyte with severe hydrogen evolution reaction. Here, we demonstrate a water-in-salt aluminum ion electrolyte (WISE) based on Al and lithium salts to tackle the above challenges. In the WISE system, water molecules can be confined within the Li+ solvation structures. This diminished Al3+-H2O interaction essentially eliminates the hydrolysis effect, effectively protecting Al anode from corrosion. Therefore, long-term Al plating/stripping can be realized. Furthermore, two types of high-performance full batteries have been demonstrated using copper hexacyanoferrate (CuHCF, a Prussian Blue Analogues) and LiNi0.8Co0.1Mn0.1O2 (NCM) as cathodes. The reversibility of Al anode laid the foundation for low cost rechargeable batteries suffering for large-scale energy storage.Broader context: Al batteries are expected to become a safe and sustainable alternative to lithium batteries. For decades, chase for a feasible Al secondary battery has not been successful. The key challenge is to find suitable cathode and electrolyte materials, together with which Al anode battery can function reversibly. Currently, fatal drawbacks have impeded the practical application of Al metal batteries (AMBs), such as sustained corrosion of Al anode and battery case in ionic liquid electrolytes, irreversibility issues as well as severe hydrogen evolution reaction during cycling in aqueous electrolyte. Therefore, electrolyte and their electrochemical kinetics play a vital role in the performance and environmental operating limitations of high-energy Al metal batteries. In this work, we demonstrate a nearly neutral Al ion water-in-salt electrolyte (WISE) to tackle the above challenges. The WISE shows excellent stability in the open atmosphere. The distinct solvation-sheath structure of Al3+ in the WISE system would protect Al metal anodes from corrosion and eliminate hydrogen evolution reaction effectively, further promoting the reversibility of Al metal anodes with dendrite-free morphology. Moreover, such a WISE exhibits superior compatibility with LiNi0.3Co0.3Mn0.3O2 (NCM) and copper hexacyanoferrate (CuHCF) cathodes and long-term stabilities with high coulombic efficiency (CE) can be attained for full batteries with the WISE. The approach in this study can furnish an opportunity to develop reversible AMBs and lay the foundation for other potential multivalent-metal-based secondary batteries suffering from interface passivation and poor reversibility, which suggest the promise of multivalent metal batteries and their applications in large-scale energy storage.