Zinc Metal Research Articles

In situ three-dimensional reconstruction and gradient-induced design of ultrastable Zn metal anodes in Zn-Se batteries

Zinc-selenium batteries have high specific and volumetric capacities, but practical development faces key challenge in achieving stable zinc metal anodes, and avoiding zinc dendrite growth, hydrogen evolution reaction (HER) and corrosion. Here, a zinc foam substrate is employed to fabricate three-dimensional gradient electrodes Zn foam@Cu@CuSe2 (ZFCCS) with gradient change of zincophilicity and conductivity. Experimental observations and simulations collectively confirm that the three-dimensional structure and gradient design effectively homogenize interfacial ion flux and diminish local current density. This optimization of the zinc deposition path synergistically fosters high flux and deep deposition of zinc metal while simultaneously preventing dendrite growth. The results demonstrate that the developed ZFCCS electrode produces an excellent Coulombic efficiency of 99.5 % over 1000 plating/stripping cycles, and the corresponding symmetric cell provides an ultra-long dendrite-free cycle life of 800 h at 5 mA cm−2 and 2 mAh cm−2 with a low overpotential of 27.4 mV. In addition, the Zn-Se full cell based on the designed ZFCCS composite anode exerts superior stable cycle life (358.1 mAh g−1 at 2 A g−1 after 1000 cycles). Therefore, the gradient design strategy based on 3D electrodes will be a reference for high performance energy storage devices.

Artificial aluminum-doped SiO2 aerogel coating layer regulating zinc ions flow for highly reversible dendrite-free zinc anodes

As a sustainable, safe, and cost-effective alternative to conventional lithium-ion batteries, aqueous rechargeable zinc-metal-based batteries have attracted significant attention in large-scale energy storage. However, their practical application is hindered by zinc anode degradation, primarily dendrite growth and corrosion, which compromise battery performance and lifespan. Herein, we present an aluminum-doped silica (Al-SiO2) aerogel coating layer to address these issues. The aluminum-doped silica aerogel coating layer offers improved hydrophilicity and zinc ion adsorption capabilities because of its porous structure, high surface area, and functional groups. By facilitating uniform zinc ion deposition and providing a physical barrier against corrosion, the Al-SiO2 aerogel coating layer significantly mitigates dendrite formation and extends the electrochemical stability and operational lifespan of aqueous rechargeable zinc-metal-based batteries. Symmetric cell tests reveal that zinc anodes coated with Al-SiO2 can achieve stable cycling over 3000 h, indicating exceptional reversibility and rate performance, much better than that of the bare Zn anode. Furthermore, the Al-SiO2 aerogel-coated zinc anode coupled with MnO2 cathode forms a stable rechargeable full battery. This work contributes to the body of knowledge on advanced materials for energy storage, highlighting the potential of aerogel coatings as a scalable and effective solution for improving the performance and durability of zinc metal anode for aqueous rechargeable zinc-metal-based batteries.

Incorporating Zinc Metal Sites in Aluminum-Coordinated Porphyrin Metal-Organic Frameworks for Enhanced Photocatalytic Nitrogen Reduction to Ammonia.

Rationally designing photocatalysts is crucial for the solar-driven nitrogen reduction reaction (NRR) due to the stable N≡N triple bond. Metal-organic frameworks (MOFs) are considered promising candidates but suffer from insufficient active sites and inferior charge transport. Herein, it is demonstrated that incorporating 3d metal ions, such as zinc (Zn) or iron (Fe) ions, into Al-coordinated porphyrin MOFs (Al-PMOFs) enables the enhanced ammonia yield of 88.7 and 65.0µggcat -1h-1, 2.5- and 1.8-fold increase compared to the pristine Al-PMOF (35.4µggcat -1h-1), respectively. The origin of ammonia (NH3) is verified via isotopic labeling experiments. Incorporating Zn or Fe into Al-PMOF generates active sites in Al-PMOF, that is, Zn-N4 or Fe-N4 sites, which not only facilitates the adsorption and activation of N2 molecules but suppresses the charge recombination. Photophysical and theoretical studies further reveal the upshift of the lowest unoccupied molecular orbital (LUMO) level to a more energetic position upon inserting 3d metal ions (with a more significant shift in Zn than Fe). The promoted nitrogen activation, suppressed charge recombination, and more negative LUMO levels in Al-PMOF(3d metal) contribute to a higher photocatalytic activity than pristine Al-PMOF. This work provides a promising strategy for designing photocatalysts for efficient solar-to-chemical conversion.

Chemical fractionation of heavy metals and zinc isotope source identification in sediments of the Huangpu River, Shanghai, China

BackgroundThe Huangpu River serves as a vital water source for around 24 million individuals residing in the metropolitan area of Shanghai. Despite this, elevated levels of heavy metals persist in the sediments of the river, with their chemical fractionation and sources remaining inadequately understood.ResultsTo improve the management of heavy metal contamination, sequential extractions and zinc (Zn) isotopic compositions were utilized to evaluate pollution levels in the Huangpu River. The findings reveal that the majority of heavy metals in the river sediments are present in residual fractions, constituting an average of 67.5% for Cd, 57.6% for Cu, 60.6% for Ni, 56.2% for Pb, and 74.4% for Cr, with the exception of Zn (33.8%). Furthermore, a substantial portion of Zn, exceeding 66%, was found in acid-exchangeable, reducible, and oxidizable fractions, indicating a high potential for Zn release into aquatic ecosystems.ConclusionFurther analysis of Zn isotopes pinpointed traffic emissions, including exhaust fumes and tire wear particles (account for ~ 34.0%), along with anthropogenic emissions and fertilizer (~ 31.7%), as the major culprits behind this contamination. These findings highlight the critical need for stricter regulations to control heavy metal contamination from traffic and domestic sources within the Huangpu River basin.

Assessment of the Impact of Heavy Metals on Clarias gariepinus Burchell and Heterobranchus longifilis Fish Species of Omambala River Basin of Anambra State Nigeria

Heavy metals are natural occurring minerals that are found in nature, as deposits in pure and mostly ore form. They are referred to as transition metals due their variable oxidation state, which as a result have made them to develop special properties among other elements in the periodic table. This study aimed to assess the levels of heavy metals (Lead, Chromium, Mercury, Cadmium, Iron, Zinc, Copper and Magnesium) in Clarias gariepinus and Hetrobrancus longifilis collected from the Omambala River. The fish samples were collected by fishermen at the fish landing site. The heavy metal analysis in the two fish species was studied using Atomic Absorbtion Spectrophotometer (AAS) and the instrument was calibrated with standard solutions. The result of this work showed that the highest compositions of heavy metals were: lead (Pb) content in C. gariepinus was 2.69±1.417 mg/l while in H. longifilis was 3.14±1.395 mg/l. However, Chromium content in C. gariepinus was 3.11±0.826 mg/l and in H. longifilis was 4.04±1.073 mg/l. Mercury in C. gariepinus was 3.98±1.903 mg/l and H. longifilis was 4.77±2.283 mg/l. Cadmium in C. gariepinus was 4.90±2.100 mg/l while H. longifilis was 4.83±2.019 mg/l. Moreover, Iron in C. gariepinus was 3.94±1.414 mg/l and H. longifilis was 4.31±2.077 mg/l. Zinc in C. gariepinus was 4.02±1.917 mg/l and H. longifilis was 5.47±2.607 mg/l. Copper in C. gariepinus was 2.62±0.720 mg/l while in H. longifilis was 3.01±0.828 mg/l. Magnesium in C. gariepinus shows 4.66±2.774 mg/l and H.longifilis shows 3.72±1.466 mg/l. The most prevalent heavy metals from the study were Zn, Cd, Hg, Mg, Fe, Cr, Pb, and Cu. It is therefore recommended that further research be made, and awareness created on the high health risk associated with frequent ingestion of these harmful mineral elements found in trace deposits in the Omambala River by the appropriate authority to ascertain their concentrations.

Adsorption of Cu(II) and Zn(II) onto ZrO2–SiO2 composite: Characteristics, mechanism and application in wastewater treatment

The presented paper describes a perspective methodology of hazardous post-production wastewater treatment focused on recovering selected metal ions species, mainly copper, zinc, and arsenic. The idea included the design of multifunctional adsorbents composed of zirconia and silica, their physicochemical evaluations, and verification tests in the adsorption process performed using model wastewaters. The proposed synthesis protocol allowed to obtain the materials with unique structural and physicochemical properties, including well-developed surface area (ABET = 398 m2∙g−1), as well as specific surface nature. It was confirmed by the results of energy dispersive X-ray, X-ray fluorescence and Fourier transform infrared spectroscopy analyses. Furthermore, by analysing the batch experiments, optimal process parameters for recovering the analyzed metal ions were established as follows: T = 313 K, pH = 5, S:L ratio = 6.67 mg:cm3, and t = 120 min. It was found that the performed removal of selected metal ion species followed pseudo-second-order kinetic and Langmuir isotherm models, and the estimated sorption capacity of the designed material was 23.5 mg∙g−1 and 12.4 mg∙g−1 for Cu(II) and Zn(II) ions, respectively. The results indicate that it is possible to separate arsenic compounds from copper and zinc ions with efficiencies of 98.9 % and 99.5 % respectively.

Highly Fluorescent π-Conjugated Azomethines and Divalent Metal Complexes as Antibacterial and Antibiofilm Nominees.

π-Conjugated azomethine ligands differing in the naphthalene or phenylmethane-centered core structure and their divalent cobalt, nickel, copper, and zinc metal complexes were prepared and well-characterized by spectral analyses in solid state. Magnetic natures of the complexes were determined by magnetic susceptibility measurements in solid-state. Their remarkable photophysical characteristics were recorded by Uv-vis and Fluorescence spectroscopic techniques. At their excitation wavelenght of 265 nm, all molecules exhibited triple fluorescence emission bands with promising intensities above 673 nm in near infra-red region. Antibacterial and antibiofilm activities of the π-conjugated azomethines are promising for potential applications in medical and healthcare settings. Hence, the antibacterial/antibiofilm activity of the π-conjugated azomethine ligands and their metal complexes against some clinically important bacteria namely Staphylococcus aureus (MSSA), Methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus epidermidis, Escherichia coli, Pseudomonas aeruginosa and Proteus mirabilis was investigated, and the obtained results have shown that the ligands and complexes had a remarkable antibacterial effect, especially on Proteus mirabilis. Metal complexes have been found to have a significant inhibitory effect on biofilm formation by MRSA, MSSA, and P. mirabilis compared to ligands. The copper (II) complex of ligand-2 showed the highest inhibition percentage, significantly reducing biofilm formation for MRSA and MSSA. Furthermore, cobalt (II) complexes of the ligands selectively inhibited the growth of the opportunistic pathogen P. mirabilis biofilms, indicating that metal complexes might be a good choice for future antibiofilm studies.

Constructing Gradient Separator to Stabilize Bi‐electrodes Toward High‐Performance Zn Metal Batteries

AbstractAqueous zinc (Zn) metal batteries have considerable potential as large‐scale energy storage systems. However, cathodic metal ions dissolution and anodic dendrite growth constrain their further development. Here, an ion gradient separator is proposed to stabilize the bi‐electrodes of Zn metal batteries. The results show that the constructed low Zn2+ concentration region in the separator helps the NH4V4O10 (NVO) model cathode to maintain good electrolyte wettability and form a N/ZnS/ZnF2‐rich cathode‐electrolyte interphase (CEI), exhibiting a low vanadium (V) dissolution behavior. Meanwhile, the high Zn2+ concentration region in the separator and the flexible solid electrolyte interphase (SEI) inhibit the dendrite growth and parasitic reactions of the Zn metal anode and further prevent the diffusion of V ions. As a proof‐of‐concept, the NVO||Zn battery with gradient separator can achieve 88.1% capacity retention even after cycling over 800 cycles at 1 A g−1, while the ordinary separator only maintains 14.8%. This work presents an innovative gradient separator strategy for achieving high‐performance Zn metal batteries and sheds light on other rechargeable batteries.

Highly stable planted MXene auxiliary layer for high-performance zinc anode deposition regulation

Aqueous zinc-ion batteries have good application prospects in large-scale energy storage, but severe dendrite behavior hinders their development. This article reports a method of planting MXene on the surface of zinc foil, that is, while mechanically polishing with a high-speed rotating wire brush, MXene solution is added dropwise, and MXene is anchored on the surface of the zinc foil with the help of a certain pressure. The MXene layer under this preparation method is stronger than the traditional self-assembled MXene layer. The MXene layer therefore acts as a physical barrier, protecting the underlying active zinc from damage. At the same time, the good hydrophilicity of the planted MXene layer reduces the concentration gradient of the interfacial electrolyte and redistributes the zinc ion flux. The unique electric field effect of MXene reduces the desolvation energy barrier, improves the transfer kinetics of Zn ions, and promotes the deposition of zinc ions in the (002) crystal plane. Experimental results show that the symmetrical battery prepared by this method can cycle stably for more than 1000 h at 0.8 mA cm−2, while its Zn\\\\Cu asymmetric battery exhibits cycle stability of more than 700 times at 0.5 mA cm−2. While maintaining a high Coulombic efficiency of over 99 %. Full cells assembled from zinc foil anodes and VO2 cathodes protected by a planted MXene layer also demonstrate higher capacity advantages. Therefore, this more stable MXene layer provides a direction for the practical application of zinc metal anodes.

A Dual Salt/Dual Solvent Electrolyte Enables Ultrahigh Utilization of Zinc Metal Anode for Aqueous Batteries.

Rechargeable aqueous zincbatteriesare promising in next-generation sustainable energy storage. However, the low zinc (Zn) metal anode reversibility and utilization in aqueous electrolytes due to Zn corrosion and poor Zn2+ deposition kinetics significantly hinder the development of Zn-ion batteries. Here, a dual salt/dual solvent electrolyte composed of Zn(BF4)2/Zn(Ac)2 in water/TEGDME (tetraethylene glycol dimethyl ether) solvents to achieve reversible Zn anode at an ultrahigh depth of discharge (DOD) is developed. An "inner co-salt and outer co-solvent" synergistic effect in this unique dual salt/dual solvent system is revealed. Experimental results and theoretical calculations provide evidence that the ether co-solvent inhibits water activity by forming hydrogen bonding with the water and coordination effects with the proton in the outer Zn2+ solvation structure. Meanwhile, the anion of zinc acetate co-salt enters the inner Zn2+ solvation structure, thereby accelerating the desolvation kinetics. Strikingly, based on the electrolyte design, the zinc anode shows high reversibility at an ultrahigh utilization of 60% DOD with 99.80% Coulombic efficiency and 9.39 mAh cm-2 high capacity. The results far exceed the performance reported in electrolyte design work recently. The work provides fundamental insights into inner co-salt and outer co-solvent synergistic regulation in multifunctional electrolytes for reversible aqueous metal-ion batteries.

Reconstruction of zinc-metal battery solvation structures operating from −50 ~ +100 °C

Serious solvation effect of zinc ions has been considered as the cause of the severe side reactions (hydrogen evolution, passivation, dendrites, and etc.) of aqueous zinc metal batteries. Even though the regulation of cationic solvation structure has been widely studied, effects of the anionic solvation structures on the zinc metal were rarely examined. Herein, co-reconstruction of anionic and cationic solvation structures was realized through constructing a new multi-component electrolyte (Zn(BF4)2-glycerol-boric acid-chitosan-polyacrylamide, simplified as ZGBCP), which incorporates double crosslinking network via the esterification, protonation and polymerization reactions, thereby combining multiple advantages of ‘liquid-like’ high conductivity, ‘gel-like’ robust interface, and ‘solid-like’ high Zn2+ transfer number. Based on the ZGBCP electrolyte, the Zn anodes achieve record-low polarization and stable cycling. Furthermore, the ZGBCP electrolyte renders the AZMBs ultrawide working temperature (−50 °C ~ +100 °C) and ultralong cycle life (30000 cycles), which further validates the feasibility of the dual solvation structure strategy and provides a innovative perspective for the development of high-performance AZMBs.

High-Capacity spatial confined deposition/stripping enabled by biphasic modulation strategy for highly reversible zinc anodes

The development of aqueous zinc ion batteries (AZIBs) faces two major challenges: dendrites Zn and parasitic reaction, which originates from the random zinc deposition at the anode interface and the abundant free H2O activity of the solvation structure. Here, we report a biphasic modulation strategy (anode interface construction and solvation structure regulation) to solve these two issues simultaneously. Through introducing trace dynamic molecular additives, the rampant alkaline zincate byproducts at the anode interface are in situ converted to three-dimensional (3D) interconnected zinc deposition/stripping templates, while the solvation structure is effectively tailored to inhibit the overactivity of electrolyte. In situ Raman and molecular dynamics simulations verify that the Zn2+ flux during the electrochemical cycles is regulated in an orderly manner, hydrogen evolution reactions (HER) and dendrites zinc growth are effectively prevented. Zinc metal deposition/stripping is effectively confined to the 3D host space by solvation structure modulation and templates guidance, thus optimizing the crystallographic and zinc metal utilization rate during electrochemistry cycling. Even under extreme conditions, such as a high (dis)charge capacity of 10 mAh cm−2, symmetrical cells assembled based on a biphasic modulation strategy maintain long-term stability of over 1000 h.

Determination of Some Minerals and Heavy metals in Raw Cow’s Milk

Milk is a healthy and nutritious food. Its ability to be consumed by all age groups and its easy accessibility increase the importance of milk in our diet. As technological developments increase, so does environmental pollution. As a result of this pollution, metals and metal mixtures reach animals and humans through the food chain. This situation negatively affects the health of living organisms. In addition, excessive intake of some mineral substances can also be toxic. The contamination of heavy metals in food occurs through various pathways. The risk of metals in the composition of the containers used in the production of acidic foods such as milk and cheese dissolving and passing into the product is more likely to occur than in other foods. For this purpose, in our research, 10 samples of raw cattle milk collected from different regions of Muş province were analyzed for the amounts of calcium, magnesium, sodium, potassium, zinc, iron, copper, manganese, and heavy metals lead and cadmium using Atomic Absorption Spectrometry device. The samples' lead, cadmium, iron, copper, and manganese contents were determined as 0.40±0.01-0.19±0.01, 0.38±0.00-0.20±0.00, 1.96±0.01-0.24±0.01, 0.50±0.00-0.11±0.00 and 0.20±0.00-0.12±0.00 mg/L, respectively. The highest levels of calcium (433.45±0.00 mg/L) and potassium (1146.25±0.02 mg/L) were detected in sample S10. The lowest levels of magnesium (197.81±0.00 mg/L) and sodium (661.17±0.01 mg/L) were found in sample S3. The zinc contents of the samples varied between 8.25±0.00-14.51±0.00 mg/L. The results obtained were evaluated considering the factors affecting the amount of mineral substances and heavy metal contamination in the milk.

Construction of an n-Type Fluorinated ZnO Interfacial Phase for a Stable Anode of Aqueous Zinc-Ion Batteries.

Aqueous rechargeable zinc-ion batteries have become an ideal solution for the next generation of energy storage systems due to their low cost and high safety. However, the uncontrollable zinc dendrites and harmful side reactions of metal zinc anodes hinder the further development of aqueous zinc-ion batteries. In this work, the artificial fluoride zinc oxide (F-ZnO) interface phase is integrated in situ on the surface of zinc foil. The F-ZnO interface phase significantly inhibits the side reactions on the surface of the zinc electrode by reducing the direct contact between the electrolyte and the surface of the zinc foil. In addition, F-ZnO modified by a small amount of F doping shows enhanced conductivity and electron transport capacity, avoiding the accumulation of high concentration Zn2+ on the anode surface, and ultimately promoting the efficient nucleation and orderly deposition of a zinc anode. The cycle life of the symmetrical cell based on F-ZnO is as high as 2600 cycles at an area current density of 4 mA cm-2, which is much better than that of a commercial pure Zn electrode. The modified F-ZnO@Zn anode truly achieves the purpose of prolonging the anode's life.

The influence of heavy metals on cytotoxicity in Tilapia zillii

The present study was designed to investigate the cytotoxic effects and bioaccumulation of heavy metals iron (Fe), zinc (Zn), copper (Cu), cadmium (Cd), lead (Pb), manganese (Mn), nickel (Ni), and chromium (Cr) in different parts (muscle, gills, and liver) of Tilapia zillii occurring in polluted drainage canal and fish farm, which is located in Abiece region in front of village number 10, Alexandria governorate, Egypt. Results of water analysis revealed the concentration of Cd, Pb, Mn, Ni, and Cr exceeded the limits defined by the American Public Health Association (APHA) in the polluted drainage canal. In addition, the concentration of Ni elevated to the standard limits of APHA and Cu was not detected in the fish farm. Different types of chromosomal aberrations were recorded (e.g., stickiness, fragmented chromosomes, centromeric gaps, chromatid break, chromatid deletion, and tetraploid). Micronucleus frequency was found to be 5.58 in the polluted drainage canal group and 0.32 in the fish farm group. Other nuclear abnormalities such as blebbed nucleus, segmented nucleus, enucleated erythrocyte, kidney-shaped nucleus, heart-shaped nucleus, polymorphic irregular nuclei, binucleated cell, nuclear fragmented erythrocyte, long nucleus, putative fragmented notched nucleus, lobed nuclei, fused erythrocytes, necrotic erythrocyte, and vacuolated nucleus were recorded. The total of erythrocytes nuclear morphological abnormalities was 70.33% in the polluted drainage canal and 1.78% in the fish farm.

The Enhancement Discharge Performance by Zinc-Coated Aluminum Anode for Aluminum–Air Battery in Sodium Chloride Solution

The main drawback of seawater batteries that use the aluminum (Al)–air system is their susceptibility to anode self-corrosion during the oxygen evolution reaction, which, in turn, affects their discharge performance. This study consist of an electrochemical investigation of pure Al, 6061 Al alloy, and both types coated with zinc as an anode in a 3.5% sodium chloride (NaCl) electrolyte. The electrolyte solution used for the deposition of zinc metal contained citrate, with and without EDTA as a complexing agent. Subsequently, the performance of the anode was tested in a seawater battery, using a carbon@MnO2 cathode and a 3.5% NaCl electrolyte. The performance of Al–air batteries has been significantly enhanced by applying a process of electrodepositing zinc (Zn) with a citrate deposition electrolyte solution in both pure aluminum and alloy 6061. The performance of the battery was further enhanced by adding EDTA as a chelating agent to the citrate-based electrolyte solution. The Al–air battery with aluminum alloy 6061 with Zn electrodeposition with an additional EDTA as the anode, carbon@MnO2 as the cathode, and NaCl 3.5% solution as the electrolyte has the highest battery performance, with a specific discharge capacity reaching 414.561 mAh.g−1 and a specific energy density reaching 0.255 mWh.g−1, with stable voltage at 0.55 V for 207 h.

Mass Transfer Limitation within Molecular Crowding Electrolyte Reorienting (100) and (101) Texture for Dendrite‐Free Zinc Metal Batteries

AbstractAqueous zinc metal batteries are emerging as a promising alternative for energy storage due to their high safety and low cost. However, their development is hindered by the formation of Zn dendrites and side reactions. Herein, a macromolecular crowding electrolyte (MCE40) is prepared by incorporating polyvinylpyrrolidone (PVP) into the aqueous solutions, exhibiting an enlarged electrochemical stability window and anti‐freezing properties. Notably, through electrochemical measurements and characterizations, it is discovered that the mass transfer limitation near the electrode surface within the MCE40 electrolyte inhibits the (002) facets. This leads to the crystallographic reorientation of Zn deposition to expose the (100) and (101) textures, which undergo a “nucleation‐merge‐growth” process to form a uniform and compact Zn deposition. Consequently, the MCE40 enables highly reversible and stable Zn plating/stripping in Zn/Cu half cells over 600 cycles and in Zn/Zn symmetric cells for over 3000 hours at 1.0 mA cm−2. Furthermore, Na0.33V2O5/Zn and α‐MnO2/Zn full cells display promising capacity and sustained stability over 500 cycles at room and sub‐zero temperatures. This study highlights a novel electrochemical mechanism for achieving preferential Zn deposition, introducing a unique strategy for fabricating dendrite‐free zinc metal batteries.

Trace Small Molecular/Nano-Colloidal Multiscale Electrolyte Additives Enable Ultra-Long Lifespan of Zinc Metal Anodes.

Electrolyte additives are efficient to improve the performance of aqueous zinc-ion batteries (AZIBs), yet the current electrolyte additives are limited to fully water-soluble additives (FWAs) and water-insoluble additives (WIAs). Herein, trace slightly water-soluble additives (SWAs) of zinc acetylacetonate (ZAA) were introduced to aqueous ZnSO4 electrolytes. The SWA system of ZAA is composed of a FWA part and a WIA part in a dynamic manner of dissolution equilibrium. The FWA part exists as soluble small molecules, which efficiently regulate Zn2+ ion solvation structure, while the WIA part exists as insoluble nano-colloids, which in-situ form a thick and robust solid electrolyte interface film on zinc metal anodes (ZMAs). Such small molecular/nano-colloidal multiscale electrolyte additives of ZAA are capable to not only improve ionic conductivity and transference number but also inhibit corrosion, hydrogen evolution, and Zn dendrite on ZMAs. The SWA-based Zn∥Zn half battery delivers a superb cumulative plating capacity of 15 Ah cm-2 under 1 mAh cm-2 and 20 mA cm-2, and the SWA-based NH4V4O10∥Zn pouch cell obtains a capacity retention of 67.8% within 4000 cycles under 4 A g-1. The study provides innovative insights for rational design of electrolyte additives, which may pave the way for the practicality of AZIBs.

Mass Transfer Limitation within Molecular Crowding Electrolyte Reorienting (100) and (101) Texture for Dendrite-Free Zinc Metal Batteries.

Aqueous zinc metal batteries are emerging as a promising alternative for energy storage due to their high safety and low cost. However, their development is hindered by the formation of Zn dendrites and side reactions. Herein, a macromolecular crowding electrolyte (MCE40) is prepared by incorporating polyvinylpyrrolidone (PVP) into the aqueous solutions, exhibiting an enlarged electrochemical stability window and anti-freezing properties. Notably, through electrochemical measurements and characterizations, it is discovered that the mass transfer limitation near the electrode surface within the MCE40 electrolyte inhibits the (002) facets. This leads to the crystallographic reorientation of Zn deposition to expose the (100) and (101) textures, which undergo a "nucleation-merge-growth" process to form a uniform and compact Zn deposition. Consequently, the MCE40 enables highly reversible and stable Zn plating/stripping in Zn/Cu half cells over 600 cycles and in Zn/Zn symmetric cells for over 3000 hours at 1.0 mA cm-2. Furthermore, Na0.33V2O5/Zn and α-MnO2/Zn full cells display promising capacity and sustained stability over 500 cycles at room and sub-zero temperatures. This study highlights a novel electrochemical mechanism for achieving preferential Zn deposition, introducing a unique strategy for fabricating dendrite-free zinc metal batteries.

The influence of age on the biological response to biodegradable zinc arterial implants

Medical devices to treat arterial diseases of older humans are routinely designed and developed using young animals. This is the case despite the significant declines of tissue regeneration, cell proliferation, and inflammation in aged humans that are not reflected in young animals. The widespread use of age-mismatched animals is particularly a concern for the testing of interactive materials, such as biodegradable metals whose dynamic interfaces continuously impact local cell and tissue regenerative processes. In order to determine the importance and impact of age differences in biodegradable stent material biocompatibility, we implanted both inert (platinum) and biodegradable (zinc) metal wires into the arteries of 1 year old and 3-month-old rats for a period of 6 months and compared the biological responses. It was found that the older animals developed a significantly larger neointimal encapsulating tissue for zinc implants vs. a smaller tissue response for the platinum implants relative to the younger rats. The neointimas of older rats contained dramatically fewer macrophages for both implant metals. The presence of neointimal smooth muscle cells was also decreased in the older rats. Endothelial cell regeneration in the old arteries was not impacted by the different metal implants. These findings demonstrate that neointimal responses to metal implants in arterial tissue are strongly impacted by age-related changes. The findings also suggest that the reliance on young animal models to evaluate metal implants intended for the arteries of considerably older individuals may substantially over predict the biocompatibility.