Aluminum Abundances Research Articles

High‐Energy‐Density Quinone‐Based Electrodes with [Al(OTF)]2+ Storage Mechanism for Rechargeable Aqueous Aluminum Batteries

AbstractRechargeable aqueous aluminum batteries (AABs) are potential candidates for future large‐scale energy storage due to their large capacity and the high abundance of aluminum. However, AABs face the challenges of inferior rate capability and cycling life due to the high charge density of Al3+, which induces the sluggish intercalation/extraction dynamics and structure collapse of inorganic cathode materials during discharge–charge cycles. Here, the optimization of macrocyclic calix[4]quinone (C4Q) with a large cavity and multi‐adjacent carbonyls structure from quinone compounds to become excellent cathode materials for high‐energy‐density AABs is reported. It exhibits a high capacity of 400 mAh g−1, a high rate capability (300 mAh g−1 at 800 mA g−1), and an excellent low‐temperature performance (224 mAh g−1 at −20 °C). The combination of experiments and theoretical calculations proves that Al(OTF)2+ cations coordinate with the carbonyl groups of C4Q during the discharge process, which can reduce desolvation penalty. Moreover, the fabricated pouch‐type Al‐C4Q battery delivers an energy density of 93 Wh kg−1cell, showing great potential for large‐scale applications. This work is expected to facilitate the application of organic cathode for AABs.

Solvent-Free and Phase-Selective Synthesis of Aluminum Trimesate Metal-Organic Frameworks.

Aluminum-based metal-organic frameworks (Al-MOFs) have shown promise as commercially valuable materials due to the variety of applications, excellent thermal, hydrothermal, and chemical stabilities, and the abundance of aluminum. In this work, for the first time, we report the solvent-free synthesis of the aluminum trimesate (Al-BTC) MOFs (MIL-100(Al), MIL-96(Al), and MIL-110(Al)) with phase selectivity and high yield. These MOFs were traditionally prepared with HF, HNO3, and bulk solvents, but these methods struggled to produce pure-phase isolations. The solvent-free strategy provides valuable insight into the future industrial scale-up production of the Al-MOFs and promotes the potential commercialization of such materials.

Rechargeable quasi-solid-state aqueous hybrid Al3+/H+ battery with 10,000 ultralong cycle stability and smart switching capability

Safe and long lifespan batteries facilitate the development of portable electronics and electric vehicles. Owing to the low-cost, naturally abundance, and trivalent charge carrier of aluminum with the highest theoretical volumetric capacity, rechargeable aqueous aluminum-ion-based batteries are considered as promising next-generation secondary batteries. However, traditional electrolytes and frequent collapse of the host structure of electrode materials greatly jeopardize the cycle stability of the batteries. Here, we develop a novel hydrogel-based electrolyte coupled with stable layered intercalation electrodes for the first time to fabricate a highly safe and flexible rechargeable hybrid Al3+/H+ battery. The as-fabricated hybrid-ion battery (HIB) delivers a high specific capacity of 125 mAh·g−1 at 0.1 A·g−1 and exhibits an unprecedented super long-term cycling stability with no capacity fading over 10,000 cycles at 2 A·g−1. In addition, the hydrogel-based electrolyte possesses smart function of thermoresponsive switching, which can effectively prevent thermal runaway for the batteries. The unprecedented long cycle stability, highly intrinsic safety as well as low-cost indicate that the flexible aqueous HIBs are promising for applications.

Mapping Alteration Mineralogy in Eastern Tsogttsetsii, Mongolia, Based on the WorldView-3 and Field Shortwave-Infrared Spectroscopy Analyses

This study produces alteration mineral maps based on WorldView-3 (WV-3) data and field shortwave-infrared (SWIR) spectroscopy. It is supported by conventional analytical methods such as X-ray diffraction, X-ray fluorescence, and electron probe X-ray micro analyzer as an initial step for mineral exploration in eastern Tsogttsetsii, Mongolia, where access is limited. Distributions of advanced argillic minerals (alunite, dickite, and kaolinite), illite/smectite (illite, smectite, and mixed-layered illite-smectite), and ammonium minerals (buddingtonite and NH4-illite) were mapped using the decorrelation stretch, band math, and mixture-tuned-matched filter (MTMF) techniques. The accuracy assessment of the WV-3 MTMF map using field SWIR data showed good WV-3 SWIR data accuracy for spectrally predominant alteration minerals such as alunite, kaolinite, buddingtonite, and NH4-illite. The combination of WV-3 SWIR mineral mapping and a drone photogrammetric-derived digital elevation model contributed to an understanding of the structural development of the hydrothermal system through visualization of the topographic and spatial distribution of surface alteration minerals. Field SWIR spectroscopy provided further detailed information regarding alteration minerals such as chemical variations of alunite, crystallinity of kaolinite, and aluminum abundance of illite that was unavailable in WV-3 SWIR data. Combining WV-3 SWIR data and field SWIR spectroscopy with conventional exploration methods can narrow the selection between deposit models and facilitate mineral exploration.

The ASAS-SN catalogue of variable stars IX: The spectroscopic properties of Galactic variable stars

ABSTRACT The All-Sky Automated Survey for Supernovae provides long baseline (∼4 yr) V-band light curves for sources brighter than V≲ 17 mag across the whole sky. We produced V-band light curves for a total of ∼61.5 million sources and systematically searched these sources for variability. We identified ∼426 000 variables, including ∼219 000 new discoveries. Most (${\sim }74{ per\ cent}$) of our discoveries are in the Southern hemisphere. Here, we use spectroscopic information from LAMOST, GALAH, RAVE, and APOGEE to study the physical and chemical properties of these variables. We find that metal-poor eclipsing binaries have orbital periods that are shorter than metal-rich systems at fixed temperature. We identified rotational variables on the main-sequence, red giant branch, and the red clump. A substantial fraction (${\gtrsim }80{ per\ cent}$) of the rotating giants have large $v$rot or large near-ultraviolet excesses also indicative of fast rotation. The rotational variables have unusual abundances suggestive of analysis problems. Semiregular variables tend to be lower metallicity ($\rm [Fe/H]{\sim }-0.5$) than most giant stars. We find that the APOGEE DR16 temperatures of oxygen-rich semiregular variables are strongly correlated with the WRP − WJK colour index for $\rm T_{eff}\lesssim 3800$ K. Using abundance measurements from APOGEE DR16, we find evidence for Mg and N enrichment in the semiregular variables. We find that the Aluminum abundances of the semiregular variables are strongly correlated with the pulsation period, where the variables with $\rm P\gtrsim 60$ d are significantly depleted in Al.

Exploring Aluminum‐Ion Insertion into Magnesium‐Doped Manjiroite (MnO2) Nanorods in Aqueous Solution

AbstractAqueous aluminum‐ion batteries are promising for sustainable energy storage given the abundance of aluminum and the ease of recycling. However, finding suitable electrode materials that can intercalate Al ions remains challenging. Here, we investigate Mg‐ion‐doped MnO2 nanorods in the manjiroite structure that allow Al‐ion insertion into the open tunnels of this material. The electrode material is characterized before and after Al‐ion insertion with X‐ray diffraction and X‐ray photoelectron spectroscopy, and the insertion process is studied via in situ transmission electron microscopy, which highlights a change in the length of the MnO2 nanorod. The results indicate that Al ions can be successfully inserted into the MnO2 nanorods, which has also been determined by density functional theory calculations to be an energetically favorable process. The electrochemical data indicate that diffusion‐controlled Al insertion as well as a surface pseudocapacitive effect occur. This indicates that MnO2 nanomaterials synthesized in the presence of metal cations is potentially a viable route for facilitating their use as electrode materials in aqueous Al‐ion batteries or supercapatteries.

The Pitfalls in Nonaqueous Electrochemistry of Al‐Ion and Al Dual‐Ion Batteries

AbstractThe quest for cost‐effective and TWh‐scale stationary energy storage systems has caused a surge of research on novel post‐Li‐ion batteries that consist solely of abundant chemical elements. Nonaqueous Al batteries, inter alia, are appealing as an inexpensive electrochemical technology owing to the high natural abundance of aluminum. A critical assessment of the literature on Al batteries, however, points to numerous misconceptions in this field. The latter is primarily linked to the false assessment of the charge storage redox reactions occurring upon cycling of Al batteries. To ensure the constructive progress of Al batteries, in this essay, the current scientific understanding of the operational mechanisms of two commonly studied Al battery systems, Al‐ion and Al dual‐ion batteries are summarized. Furthermore, the main pitfalls in interpretation and reporting of the electrochemical performance of Al cathode materials and cell‐level energy densities of Al batteries are clarified along with core challenges currently limiting their development. Toward this end, the subject of the charge storage balancing of Al dual‐ion batteries is discussed.

An overview and prospective on Al and Al-ion battery technologies

Aluminum batteries are considered compelling electrochemical energy storage systems because of the natural abundance of aluminum, the high charge storage capacity of aluminum of 2980 mA h g−1/8046 mA h cm−3, and the sufficiently low redox potential of Al3+/Al. Several electrochemical storage technologies based on aluminum have been proposed so far. This review classifies the types of reported Al-batteries into two main groups: aqueous (Al-ion, and Al-air) and non-aqueous (aluminum graphite dual-ion, Al-organic dual-ion, Al-ion, and Al-sulfur). Specific focus is given to Al electrolyte chemistry based on chloroaluminate melts, deep eutectic solvents, polymers, and “chlorine-free” formulations.

Aluminum Metal-Organic Frameworks with Photocatalytic Antibacterial Activity for Autonomous Indoor Humidity Control.

There is an increasing need to maintain the indoor humidity at a comfortable and healthy level without relying on high energy-consuming and potentially germ-infested air-conditioning systems. Water adsorbents exhibiting reversible moisture adsorption/desorption ability as well as sufficient antibacterial activity are highly expected to achieve humidity control in an autonomous and safe way. Metal-organic frameworks (MOFs) featuring high porosity and designability show potential in meeting these requirements in a singular platform. Given the low toxicity and the rich abundance of aluminum in nature, a family of isoreticular Al-terephthalate-based MOFs were systematically evaluated in terms of the static and kinetic water adsorption/desorption and the photocatalytic bacteria-killing behavior. In particular, CAU-1-OH exhibits a desired working range (40-60% RH), a high working capacity (0.41 g g-1), an excellent cycle performance (500 cycles), and a high photocatalytic killing efficiency (99.94%) against Escherichia coli. As a proof of concept, the air filter prepared by coating CAU-1-OH on a commercial nonwoven fabric is capable of buffering against sudden humidity changes caused by the infiltration of outside air and effectively reducing the contamination of bioaerosol or particulate matter. The study significantly advanced the development of next-generation water adsorbents with antibacterial activity for residential humidity control.

Two-Dimensional Covalent Organic Frameworks with Enhanced Aluminum Storage Properties.

Aluminum-ion batteries (AIBs) are regarded as one of the most promising types of energy storage device in light of the safety, natural abundance, and electrochemical properties of aluminum. However, the rate capabilities of AIBs are limited owing to the sluggish kinetics of chloroaluminate anions. In this study, a covalent organic framework (COF) is adopted as the cathode material in AIBs. Theoretical and experimental results suggest that the COFs allow fast anion diffusion and intercalation without structure collapse, owing to the robust frameworks and the hierarchical pores with a large specific surface area of 1794 m2 g-1 . The resultant AIB exhibits remarkable long-term stability, with a reversible discharge capacity of 150 mAh g-1 after 13 000 cycles at 2 A g-1 . It also shows an excellent rate capability of 113 mAh g-1 at 5 A g-1 . This work fully demonstrates the potential of COFs in the storage of chloroaluminate anions and other large-sized ions.

A Critical Evaluation of the Effect of Electrode Thickness and Side Reactions on Electrolytes for Aluminum-Sulfur Batteries.

The high abundance and low cost of aluminum and sulfur make the Al–S battery an attractive combination. However, significant improvements in performance are required, and increasing the thickness and sulfur content of the sulfur electrodes is critical for the development of batteries with competitive specific energies. This work concerns the development of sulfur electrodes with the highest sulfur content (60 wt %) reported to date for an Al–S battery system and a systematic study of the effect of the sulfur electrode thickness on battery performance. If low‐cost electrolytes made from acetamide or urea are used, slow mass transport of the electrolyte species is identified as the main cause of the poor sulfur utilization when the electrode thickness is decreased, whereas complete sulfur utilization is achieved with a less viscous ionic liquid. In addition, the analysis of very thin electrodes reveals the occurrence of degradation reactions in the low‐cost electrolytes. The new analysis method is ideal for evaluating the stability and mass transport limitations of novel electrolytes for Al–S batteries.

Designing two-dimensional WS2 layered cathode for high-performance aluminum-ion batteries: From micro-assemblies to insertion mechanism

The novel star-shaped 2D WS 2 microsheet assemblies are explored as promising cathode material for aluminum-ion batteries. Their aluminum reactivity mechanism involving reaction AlCl 4 − and S 2− anions has been understood via DFT calculations, ex-situ XPS and XRD. • Novel approach for designing of the star-shaped 2D WS 2 microsheet assembly. • Deep insights into the intercalation mechanism of chloroaluminate anions in 2D cathode. • Remarkable cycling stability with high reversible capacities of the 2D WS 2 microsheets-assembled cathode for AIBs. Owing to the high abundance, inherent safety, and three-electron redox properties of aluminum, aluminum-ion batteries (AIBs) are promising candidates for the next-generation battery technologies with high energy-to-price ratio. Despite recent great progress in finding appropriate electrolyte, an on-going research focus of the AIBs remains to be exploiting host electrodes for the large aluminum (complex) ions. Herein, a star-shaped two-dimensional (2D) WS 2 microsheet assembly cathode substitute is prepared and applied in AIBs for the first time. The in-depth study with density functional theory (DFT) calculations, ex-situ X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) reveals an explicit intercalation mechanism of chloroaluminate anions (AlCl 4 − ) in the WS 2 electrode. Benefiting from their structural configuration, the star-shaped 2D WS 2 microsheet assemblies display a highly reversible capacity of 254 mA h g −1 at a current density of 0.1 A g −1 , a superior rate capability (86 mA h g −1 at 5 A g −1 ), and a favorable cycling stability (119 mA h g −1 remained after 500 cycles at 1 A g −1 ). The synthetic approach and the proposed mechanism could pave the way for the further development of high-performance AIBs.

The Abundances of Aluminum and Mercury of β Scl derived from its far Ultraviolet Spectrum

The Abundances of Aluminum and Mercury of β Scl derived from its far Ultraviolet Spectrum

Size- and Surface-Dependent Photoresponses of Solution-Processed Aluminum Nanoparticles

Plasmonic aluminum nanoparticles have emerged as an exciting new materials platform, due to the high natural abundance of aluminum, their ability to be synthesized in the solution phase, and the potential of these materials to be used for photocatalysis and sensing. However, the photothermal properties of solution-processed aluminum nanoparticles, particularly how phonon energy transfer depends on particle size and surface properties, are critical for practical applications and are currently unexplored. Here, we use transient absorption spectroscopy, in combination with simulations of phonon and thermal energy dissipation, to investigate the photoresponses of aluminum nanoparticles of various diameters (54, 85, 121, and 144 nm) suspended in 2-propanol. Fast thermal transfer rates to the solvent (170-280 ps) are observed for particles of all sizes and are facilitated by native oxide coverage, as verified with a two-interface thermal energy-transfer model. Size-dependent phonon “breathing”/vibrational modes...

Serum metallome in pregnant women and the relationship with congenital malformations of the central nervous system: a case-control study

BackgroundCongenital malformations of the central nervous system (CNS) consist of a wide range of birth defects of multifactorial origin.MethodsConcentrations of 44 metals were determined by Inductively Coupled Plasma Mass Spectrometry in serum of 111 mothers in the second trimester of pregnancy who carried a malformed fetus and compared them with serum concentrations of the same metals in 90 mothers with a normally developed fetus at the same week of pregnancy.Data are reported as means ± standard deviations.ResultsWe found a direct relationship between congenital defects of the CNS and maternal serum concentration of aluminum: it was statistically higher in women carrying a fetus with this class of malformation, compared both to mothers carrying a fetus with another class of malformation (6.45 ± 15.15 μg/L Vs 1.44 ± 4.21 μg/L, p < 0.0006) and to Controls (i.e. mothers carrying a normally-developed fetus) (6.45 ± 15.15 μg/L Vs 0.11 ± 0.51 μg/L, p < 0.0006). Moreover, Aluminum abundances were below the limit of detection in the majority of control samples.ConclusionCAluminum may play a role in the onset of central nervous system malformations, although the exact Aluminum species and related specific type of malformation needs further elucidation.

Thick electrodes upon biomass-derivative carbon current collectors: High-areal capacity positive electrodes for aluminum-ion batteries

Rechargeable aluminum-ion batteries (AIBs) are considered as low-cost safe energy storage devices beyond lithium-ion batteries, due to the high volumetric capacity and rich abundance of aluminum. However, the highly corrosive room temperature ionic liquid electrolyte causes serious problems in the traditional metal current collectors, and electrochemical inert metals with higher density have been commonly used, which leads to dramatic decreased material utilization in the positive electrode. For addressing such issues, here a biomass-derivative carbon (BDC) current collector is demonstrated to construct millimeter-scale thick positive electrodes based on two types of graphite active materials (with different planar sizes) and two electrode configurations. The results suggest the strategy of using single-side casting process with graphite of smaller planar size would be more promising to promote the overall electrochemical properties and energy storage performance. The as-assembled thick electrode (with thickness up to ∼2 mm) using the same type of graphite is able to deliver much enlarged areal loading (36 mg cm−2), showing greater areal capacity for energy storage. The strategy and mechanism in this work offers a considerable approach for improving the current collectors and promoting the graphite proportion in AIBs.

Chemodynamics of newly identified giants with a globular cluster like abundance patterns in the bulge, disc, and halo of the Milky Way

ABSTRACT The latest edition of the APOGEE-2/DR14 survey catalogue and the first Payne data release of APOGEE abundance determinations by Ting et al. are examined. We identify 31 previously unremarked metal-poor giant stars with anomalously high levels of [N/Fe] abundances, which is not usually observed among metal-poor stars in the Milky Way. We made use of the Brussels Automatic Stellar Parameter (BACCHUS) code to re-derive manually the chemical abundances of 31 field stars in order to compile the main element families, namely the light elements (C, N), a-elements (O, Mg, Si), iron-peak element (Fe), s-process elements (Ce, Nd), and the light odd-Z element (Na, Al). We have found all these objects have a [N/Fe] ≳ +0.5, and are thus identified here as nitrogen-rich stars. An orbital analysis of these objects revealed that a handful of them shares the orbital properties of the bar/bulge, and possibly linked to tidal debris of surviving globular clusters trapped into the bar component. Three of the 31 stars are actually halo interlopers into the bulge area, which suggests that halo contamination is not insignificant when studying N-rich stars found in the inner Galaxy, whereas the rest of the N-rich stars share orbital properties with the halo population. Most of the newly identified population exhibits chemistry similar to the so-called second-generation globular cluster stars (enriched in aluminum, [Al/Fe] ≳ +0.5), whereas a handful of them exhibit lower abundances of aluminum, [Al/Fe] &amp;lt; +0.5, which are thought to be chemically associated with the first generation of stars, as seen in globular clusters, or compatible with origin from a tidally disrupted dwarf galaxy.

The Relationship between Globular Cluster Mass, Metallicity, and Light-element Abundance Variations

We investigate aluminum abundance variations in the stellar populations of globular clusters using both literature measurements of sodium and aluminum and APOGEE measurements of nitrogen and aluminum abundances. For the latter, we show that the Payne is the most suitable of the five available abundance pipelines for our purposes. Our combined sample of 42 globular clusters spans approximately 2 dex in [Fe/H] and 1.5 dex in $\log{M_{GC}/M_{\odot}}$. We find no fewer than five globular clusters with significant internal variations in nitrogen and/or sodium with little-to-no corresponding variation in aluminum, and that the minimum present-day cluster mass for aluminum enrichment in metal-rich systems is $\log{M_{GC}/M_{\odot}} \approx 4.50 + 2.17(\rm{[Fe/H]}+1.30)$. We demonstrate that the slopes of the [Al/Fe] vs [Na/Fe] and [Al/Fe] vs [N/Fe] relations for stars without field-like abundances are approximately log-linearly dependent on both the metallicity and the stellar mass of the globular clusters. In contrast, the relationship between [Na/Fe] and [N/Fe] shows no evidence of such dependencies. This suggests that there were (at least) two classes of non-supernovae chemical polluters that were common in the early universe, and that their relative contributions within globular clusters somehow scaled with the metallicity and mass of globular clusters. The first of these classes is predominantly responsible for the CNO and NeNa abundance variations, and likewise the second for the MgAl abundance variations. 47 Tuc and M4 are particularly striking examples of this dichotomy. As an auxiliary finding, we argue that abundance variations among Terzan 5 stars are consistent with it being a normal globular cluster.

The relationship between globular cluster parameters and abundance variations

AbstractWe discuss a meta-analysis of the association of abundance variations in globular cluster stars with the present-day stellar mass and metallicity of globular clusters. Using data for 42 globular clusters that are well-sampled from either or both of prior literature studies and the APOGEE survey, we confirm prior findings that increasing aluminum abundance variations in globular clusters are positively correlated with increasing present-day stellar mass or decreasing metallicity. We also demonstrate that the ratio of aluminum abundance variations to either nitrogen abundance variations or sodium abundance variations is itself positively correlated with decreasing metallicity and increasing stellar mass of globular clusters. This suggests that there were at least two non-supernovae chemical polluters that were active in the early universe.

High-resolution observations of gas and dust around Mira using ALMA and SPHERE/ZIMPOL

Context. The outflows of oxygen-rich asymptotic giant branch (AGB) stars are thought to be driven by radiation pressure due to the scattering of photons on relatively large grains, with sizes of tenths of microns. The details of the formation of dust in the extended atmospheres of these stars and, therefore, the mass-loss process, is still not well understood. Aims. We aim to constrain the distribution of the gas and the composition and properties of the dust grains that form in the inner circumstellar environment of the archetypal Mira variable o Cet. Methods. We obtained quasi-simultaneous observations using ALMA and SPHERE/ZIMPOL on the Very Large Telescope (VLT) to probe the distribution of gas and large dust grains, respectively. Results. The polarized light images show dust grains around Mira A, but also around the companion, Mira B, and a dust trail that connects the two sources. The ALMA observations show that dust around Mira A is contained in a high-gas-density region with a significant fraction of the grains that produce the polarized light located at the edge of this region. Hydrodynamical and wind-driving models show that dust grains form efficiently behind shock fronts caused by stellar pulsation or convective motions. The distance at which we observe the density decline (a few tens of au) is, however, significantly larger than expected for stellar-pulsation-induced shocks. Other possibilities for creating the high-gas-density region are a recent change in the mass-loss rate of Mira A or interactions with Mira B. We are not able to determine which of these scenarios is correct. We constrained the gas density, temperature, and velocity within a few stellar radii from the star by modelling the CO v = 1, J = 3−2 line. We find a mass (~3.8 ± 1.3) × 10−4 M⊙ to be contained between the stellar millimetre photosphere, R⋆338 GHz, and 4 R⋆338 GHz. Our best-fit models with lower masses also reproduce the 13CO v = 0, J = 3−2 line emission from this region well. We find TiO2 and AlO abundances corresponding to 4.5% and &lt;0.1% of the total titanium and aluminium expected for a gas with solar composition. The low abundance of AlO allows for a scenario in which Al depletion into dust happens already very close to the star, as expected from thermal dust emission observations and theoretical calculations of Mira variables. The relatively large abundance of aluminium for a gas with solar composition allows us to constrain the presence of aluminium oxide grains based on the scattered light observations and on the gas densities we obtain. These models imply that aluminium oxide grains could account for a significant fraction of the total aluminium atoms in this region only if the grains have sizes ≲0.02 μm. This is an order of magnitude smaller than the maximum sizes predicted by dust-formation and wind-driving models. Conclusions. The study we present highlights the importance of coordinated observations using different instruments to advance our understanding of dust nucleation, dust growth, and wind driving in AGB stars.