Zinc Deposits Research Articles

β''-Al2O3 protecting layer for stable zinc metal anodes

Aqueous zinc-ion batteries (AZIB) has attracted considerable attention on account of its low cost, high security and environmental friendliness. Nevertheless, the growing dendrites and corrosion reactions on the surface of zinc anode limit the development of AZIB. Herein, β''-Al2O3 with high ion conductivity was firstly employed as an efficient artificial layer for stabilizing the zinc anode. The optimized β''-Al2O3 layer enables homogeneous ion flux and uniform zinc deposition, significantly suppressing dendrite growth and parasitic reactions. Symmetric cells based on this unique protective layer can stably operate for 1600 h under 1 mA cm−2/1 mAh cm−2. Benefiting from the high-performance zinc metal anode, the full cell paired with the NH4V4O10 cathode delivers a high discharge initial capacity of 400 mAh g−1 at 1 A g−1 and good cycling stability. This simple protecting layer provides a new strategy for the modification of zinc metal anode and accelerates the practical application of AZIB.

Polymer-based passive layer to stabilize zinc anode in aqueous electrolyte

Metallic zinc holds promise as a cost-effective and scalable material for secondary energy storage applications. However, its inherent reversibility issues hinder its practical implementation. Among various strategies, interface engineering has emerged as a promising approach to enhance the reversibility of zinc anodes. Herein we introduce an innovative method involving the parallel deposition of poly(acrylic acid) (PAA) and zinc metal, creating a composite layer of polymer and zinc, denoted as Zn-PAA. This unique Zn-PAA layer deposition technique remarkably enhances interfacial behavior, ensuring superior cyclic stability in symmetric cells. Moreover, the Zn-PAA layer reduces polarization effects and effectively mitigates interface alterations during plating and stripping processes resulting in increased interface stability. This study highlights the potential of simultaneous electropolymerisation and zinc deposition as a promising strategy to coat and densify interface on zinc anode with intertangled matrix of zinc and polymer for improving the performance and stability of zinc anodes in batteries.

Increasing the Cycle Life of Zinc Metal Anodes and Nickel-Zinc Cells Using Flow-Through Alkaline Electrolytes

Alkaline electrolyte flow through porous Zn anodes and Ni(OH)2 cathodes can overcome diffusion limits, reduce dendrite growth, and improve cycle life. Zinc deposition morphology improves with low flow rates electrolyte in KOH/ZnO electrolytes at current densities near the diffusion-limit regime. Zinc dendrites present without flow are suppressed by micrometer-per-second flow at concentrations ranging from 0.2 to 0.6 M ZnO dissolved in 6 M and 10 M KOH solutions. Zn-Cu asymmetric cell tests reveal that flowing electrolyte increases the lifespan by more than 6 times in the diffusion-limit regime by suppressing gas evolution and dendrite formation. Ni-Zn cell tests show that a flow-assisted battery cycles 1500 times with over 95% Coulombic efficiency (CE) at 35 mA cm−2 current density and 7 mAh/cm2 charge capacity, increasing the battery lifespan by 17 times compared with a stagnant Ni-Zn cell. Flow-through electrolyte also stabilizes the Zn electrode in the over-limiting regime, achieving approximately 4 times increased lifespan and 297 cycles with over 90% CE at 52 mA cm−2.

Dual effect of organic/inorganic artificial protective layer to construct high-performance zinc metal anode

Owing to their high specific capacity, low cost, environmental friendliness and safety, aqueous zinc ion batteries (AZIBs) have been one of the most popular battery systems. Nevertheless, dendrite growth, corrosion, hydrogen evolution and passivation on the anode side can seriously affect the lifetime of AZIBs. In view of this, this work constructs a protective layer compounded from inorganic (titanium silicate molecular sieve, TS) and organic (polyacrylonitrile, PAN) materials to realize the high-performance and dendrite-free zinc anode (Zn@PAN-TS). The cyano group in PAN has a coordination effect with zinc ions, which facilitates the transport of zinc ions. The porous TS can regulate the zinc ion flux through ion-confinement effect. Thus, the PAN-TS composite protective layer provides fast and orderly ion transport channels that modulate the uniform deposition of zinc through dual effect. Moreover, the experimental results show that the Zn@PAN-TS 50:1 anode has the best electrochemical performance. The corresponding MnO2 full cell maintained a high discharge capacity of 217.2 mAh·g−1 with a high retention rate of 81.1 % after 500 cycles at 0.3 A·g−1. This strategy offers fresh insight into constructing multifunctional hybrid interface for dendrite-free AZIBs.

Electroless brassing of historical artefacts

Abstract The topic of this work was the investigation of an alternative brassing technique consisting of electroless zinc plating of a copper object in a strongly alkaline solution and subsequent annealing to achieve a characteristic brass appearance. Within the scope of the work was the determination of the mechanism of zinc deposition on the copper surface, the optimisation of the NaOH concentration (30 and 40 wt. %), time of deposition (5-120 min), as well as temperature (150 and 200 °C) and annealing time (15 – 60 min). Electrochemical methods (potentiodynamic curves and open-circuit potential), metallography, X-ray diffraction (XRD), and glow-discharge optical emission spectroscopy (GD-OES) were used to study the brassing mechanism. Electrochemical measurements have shown that zinc powder significantly decreases the surface potential of copper to the value of zinc itself and also acts as a reducing agent. The diffusion of zinc in copper was found to occur during the primary deposition of zinc with the formation of the γ phase (Cu5Zn8). The optimal NaOH concentration is 40 wt.% and the deposition time is 60 min. The optimal conditions of annealing are 200 °C and 60 min. The primary γ phase is transformed during the annealing process into β and α phases.

Synergistic interaction between amphiphilic ion additive groups for stable long-life zinc ion batteries

The uneven deposition of zinc and hydrogen generation at the zinc anode interface constitute major impediments to the lifespan of aqueous zinc-ion batteries. Herein, an amphoteric ion additive, choline phosphate (CP), is proposed to stabilize the battery anode interface. The remarkable interplay between choline ions and phosphate groups assumes a pivotal role in homogenizing zinc ion deposition and regulating the behavior of free water molecules. Due to the negative electric field adsorption on the surface of the zinc anode, the positively charged choline ions will be adsorbed on its surface preferentially and prevent the approach of water molecules. The phosphate group interacts strongly with the zinc ion, permeating the solvated structure of these ions, regulating zinc ion flux, and immobilizing free water molecules through hydrogen bonding to impede unwanted side reactions. In summary, using CP additives yields a profound enhancement in enabling significantly extended cycle lifespans of both Zn//Zn symmetric batteries and LiFePO4 full batteries.

Dendrite-free anodes enabled by MOF-808 and ZIF-8 modified glass microfiber separator for ultralong-life zinc-ion hybrid capacitors

Zinc-ion hybrid capacitors (ZIHCs) have been attracted attention for aqueous electrochemical energy storage systems owing to their high safety, low cost, abundant natural resource of zinc, convenient assembly (in an air atmosphere), robust stability with aqueous electrolytes, and the unique electrochemical characteristics of metallic zinc (Zn) as an anode electrode. Nevertheless, the growth of dendrite is the main challenge of zinc electrode in an aqueous electrolyte, leading to short circuit failure. Herein, metal-organic frameworks (MOFs) have been employed to decorate the separator. The porous nature of MOFs has been identified as beneficial for directing uniform zinc deposition. This study focuses on the operational efficiency and lifecycle of ZIHCs utilizing MOFs, specifically MOF-808 and ZIF-8, to modify glass microfiber separators. The results demonstrated that the symmetrical cell using MOF modified separators exhibited high performance, maintaining stable voltage over 1000 h. attributed to the enhanced uniformity of Zn ion flux during striping/plating processes. Additionally, at the current density of 1.0 A g−1, ZICs with MOFs modified separators exhibited higher specific capacities compared to those using the pristine separator and prolonged the cycle life over 20,000 cycles with capacity retention of 56.73 and 63.89 %, respectively. Because the MOFs modified separators can inhibit non-uniform dendritic zinc growth on a zinc anode surface according to the scanning electron micrographs.

Mineralization processes of the Mount Garnet Zinc deposit, NE Queensland (Australia): Insights from garnet geochemistry and U-Pb geochronology

The Mount Garnet Zinc deposit in NE Queensland, Australia, is located in the region of voluminous magmatism associated with the formation of Palaeozoic continental arcs of Gondwana. Ore-forming events of this deposit are related to the intrusion of the Kennedy Igneous Association (KIA) – a large suite of igneous rocks spanning Late Carboniferous to Early Permian in age – into the Silurian limestone (Chillagoe Formation) in the Hodgkinson Province (Mossman Orogen). Petrographic observations and in situ major and trace element analysis reveal the sequence of garnet growth and fluid-rock interaction during skarn formation. Three types of garnets are identified, Grt I (including IA and IB) and Grt II. Grt IB is related to Zn-Pb mineralization. All garnets have elevated Sn and W and the highest levels of W and Sn are observed in Grt II. Garnet U-Pb ages of Grt IB provide the first direct geochronological result of hydrothermal minerals in the Mount Garnet region. New data argues that the base metal mineralization may take place during early Permian period and be sourced from the Claret Creek Supersuite. Sn-W mineralization may be associated with the O’Briens Creek Supersuite.

Artificial Hydrophilic Organic and Dendrite-Suppressed Inorganic Hybrid Solid Electrolyte Interface Layer for Highly Stable Zinc Anodes.

Aqueous zinc-ion batteries (AZIBs) have gained significant attentions for their inherent safety and cost-effectiveness. However, challenges, such as dendrite growth and anodic corrosion at the Zn anode, hinder their commercial viability. In this paper, an organic-inorganic coating layer (Nafion-TiO2) was introduced to protect the Zn anode and electrolyte interface. Briefly, Nafion effectively shields against the corrosion from water molecules through the hydrophobic wall of -CF3 and guided zinc deposition from the -SO3 functional group, while TiO2 particles with a higher Young's modulus (151 GPa vs 120 GPa from Zn metal) suppress the zinc dendrite formation. As a result, with the protection of Nafion-TiO2, the symmetrical Zn∥Zn battery shows an improved cycle life of 1,750 h at 0.5 mA cm-2, and the full cell based on Zn∥MnO2 shows a long cycle life over 1,500 cycles at 1 A g-1. Our research offers a novel approach for protecting zinc metal anodes, potentially applicable to other metal anodes such as those in lithium and sodium batteries.

Anion‐Regulated Electric Double Layer and Progressive Nucleation Enable Uniform and Nanoscale Zn Deposition for Aqueous Zinc‐Ion Batteries

AbstractAqueous zinc‐ion batteries have been regarded as safe and cheap energy storage devices. However, severe zinc dendrite growth and water decomposition limit the sustainability of aqueous zinc‐ion batteries. Herein, sodium‐difluoro(oxalato)borate (NaDFOB) is introduced into ZnSO4 electrolyte to modify the electric double layer (EDL) and the nucleation mechanism. Electrochemical tests and density functional theory calculations reveal that DFOB− adsorbs on the zinc electrode to form a water‐poor EDL, effectively suppressing side reactions. Notably, a detailed investigation of zinc deposition demonstrates that the adsorbed DFOB− ions induce progressive nucleation, resulting in nanoscale zinc nuclei and uniform zinc growth. Additionally, the adsorbed DFOB− ions decompose into a solid electrolyte interphase, further protecting the zinc electrode. Consequently, the Zn/Zn symmetric cell using ZnSO4/NaDFOB electrolyte can cycle for over 500 h at 5 mA cm−2 to reach a capacity of 10 mAh cm−2, while a Zn/Cu half cell maintains an average Coulombic efficiency of 99.3% over 400 cycles. A high capacity retention of 93.0% with a capacity of 250 mAh g−1 at 0.2 A g−1 is achieved in the ZnSO4/NaDFOB electrolyte in full cell cycling. These findings highlight the impact of anion‐modified EDL and progressive nucleation on achieving highly uniform zinc deposition.

Use of Polyacrylonitrile as Anodic Artificial Solid Electrolyte Interphase for Aqueous-Based Zinc-Ion Batteries

Rechargeable aqueous zinc-ion batteries (ZIBs) have attracted attention for energy storage systems because of their high specific capacity, low cost, and safety. However, practical application of the zinc anode in mild acidic electrolytes is limited by several issues such as dendrite formation, corrosion, hydrogen evolution reaction, passivation and relatively low cycling performance. Coating the zinc anode with graphite (GP) can partially solve these issues and improves the cycling performance of ZIB. However, after long-term charge/discharge cycles, zinc tends to migrate and redeposit over the surface of GP owing to the electronic conductivity of GP particles. Thus, after long-term cycling, the issues mentioned are back. Fabrication of artificial solid electrolyte interphase (ASEI) on the surface of the zinc anode shows high potential for solving these issues. In this work, polyacrylonitrile (PAN) with zinc trifluoromethanesulfonate (Zn(CF3SO3)2) (PANZ) as ASEI was coated on the GP layer onto the zinc anode (PANZ@GP@Zn), and compared with the anode having GP coated layers and pristine zinc anode. The coating layer was prepared by the doctor blading method. The result showed that the PANZ@GP@Zn anode can reduce zinc deposition over the anode surface when compared with the GP@Zn anode, leading to the high cycling stability of ZIBs and extending the battery's life.

Surface Patterning of Metal Zinc Electrode with an In-Region Zincophilic Interface for High-Rate and Long-Cycle-Life Zinc Metal Anode

HighlightsA stable Zn anode was obtained by patterning Zn foil surfaces and endowing a zincphilic interface in microchannels.The accumulation of electrons in the microchannel and the zincphilic interface promoted preferential heteroepitaxial Zn deposition in the microchannel region and subsequent homoepitaxial Zn deposition on the array surface.The Zn symmetrical cells could undergo repeated plating/stripping for more than 25,000 cycles at the current densities of 10 and 20 mA cm−2.

Tailoring crystallization zinc hydroxide sulfates growth towards stable zinc deposition chemistry

Tailoring crystallization zinc hydroxide sulfates growth towards stable zinc deposition chemistry

Toward a Metal Anode-Free Zinc-Air Battery for Next-Generation Energy Storage.

Rechargeable aqueous zinc-air batteries (ZABs) promise high energy density and safety. However, the use of conventional zinc anodes affects the energy output from the battery, so that the theoretical energy density is not achievable under operation conditions. A large portion of the zinc is shielded by anode passivation during the discharge process and remains electrochemically unused, making the operation of rechargeable ZABs inefficient up to date. In a metal anode-free ZAB, there is no unnecessary excess zinc if the zinc reservoir can be precisely adjusted by electrodeposition of zinc from the electrolyte. In this respect, an anode-free battery uses the electrolyte offering a dual-mode functionality not only providing ionic conductivity but also being the source of zinc. In addition, it is shown that a defined porous anode architecture is crucial for high rechargeability in this new type of ZAB. 3D-spatially arranged carbon nanotubes as geometrically defined host structures allow a homogeneous zinc deposition from the electrolyte. Together with carbon nanohorns as an active 2e- catalyst on the cathode side, the rechargeability of this new concept reaches up to 92%.

Horizontally Arranged Zn Platelet Deposition Regulated by Bi2O3/Bi toward High-Rate and Dendrite-Free 3D Zn Composite Anode.

Aqueous Zn-metal battery is considered as a promising energy-storage system. However, uncontrolled zinc dendrite growth is the main cause of short-circuit failure in aqueous Zn-based batteries. One of the most efficient and convenient strategies to alleviate this issue is to introduce appropriate zincophilic nucleation sites to guide zinc metal deposition and regulate crystal growth. Herein, this work proposes Bi2O3/Bi nanosheets anchored on the cell wall surface of the 3D porous conductive host as the Zn deposition sites to modulate Zn deposition behavior and hence inhibit the zinc dendrite growth. Density functional theory and experimental results demonstrate that Bi2O3 has a super zinc binding energy and strong adsorption energy with zinc (002) plane, as a super-zincophilic nucleation site, which results in the deposition of zinc preferentially along the horizontal direction of (002) crystal plane, fundamentally avoids the formation of Zn dendrites. Benefiting from the synergistic effect Bi2O3/Bi zincophilic sites and 3D porous structure in the B-BOGC host, the electrochemical performance of the constructed Zn-based battery is significantly improved. As a result, the Zn anode cycles for 1500cycles at 50mAcm-2 and 1.0 mAhcm-2. Meanwhile, the Zn@B-BOGC//MnO2 full cell can operate stably for 2000 cycles at 2.0Ag-1.

Ion Sieve Interface Assisted Zinc Anode with High Zinc Utilization and Ultralong Cycle Life for 61 Wh/kg Mild Aqueous Pouch Battery.

The cycling stability of a thin zinc anode under high zinc utilization has a critical impact on the overall energy density and practical lifetime of zinc ion batteries. In this study, an ion sieve protection layer (ZnSnF@Zn) was constructed in situ on the surface of a zinc anode by chemical replacement. The ion sieve facilitated the transport and desolvation of zinc ions at the anode/electrolyte interface, reduced the zinc deposition overpotential, and inhibited side reactions. Under a 50% zinc utilization, the symmetrical battery with this protection layer maintained stable cycling for 250 h at 30 mA cm-2. Matched with high-load self-supported vanadium-based cathodes (18-20 mg cm-2), the coin battery with 50% zinc utilization possessed an energy density retention of 94.3% after 1000 cycles at 20 mA cm-2. Furthermore, the assembled pouch battery delivered a whole energy density of 61.3 Wh kg-1, surpassing the highest mass energy density among reported mild zinc batteries, and retained 76.7% of the energy density and 85.3% (0.53 Ah) of the capacity after 300 cycles.

Boosting Ion Diffusion and Charge Transfer by Zincophilic Accordion Arrays to Achieve Ultrafast Aqueous Zinc Metal Batteries

AbstractA key challenge to apply aqueous zinc metal batteries (AZMBs) as next‐generation energy storage device is to improve the rechargeability at high current densities, which is needed to circumvent slowly ion diffusion in anode and sluggish charge transfer of Zn2+. Herein, a zincophilic accordion array derived from MOF is developed as zinc host for simultaneously boosted ion diffusion and charge transfer. The designed host is prepared by etching and disproportionation reactions, the abundant zincophilic Sn sites with nano‐size uniform disperse on accordion arrays nanosheets (Sn‐AA). Then a composite Zn anode (Sn‐AA@Zn) is obtained by compacting Sn‐AA host with zinc power (Zn‐P). The Sn‐AA@Zn anode has an ultra‐low activation energy (37.1 kJ mol−1) and nucleation overpotential (10 mV), achieving fast charge transfer of Zinc deposition. In addition, the cycle life of the symmetric cell with Sn‐AA@Zn anode exceeds 13 000 cycles at 50 mA cm−2, which is 32 times than that of the Zn‐P anode. And the full cell with Sn‐AA@Zn anode and MnO2 cathode maintains a capacity of 122 mAh g−1 after 5000 cycles at 5 Ag−1. Hopefully, the 3D anode based on Sn‐AA@Zn accordion array and Zn‐P has significantly improved the rechargeability of AZMB at high current density.

An extended substrate screening strategy enabling a low lattice mismatch for highly reversible zinc anodes

Aqueous zinc batteries possess intrinsic safety and cost-effectiveness, but dendrite growth and side reactions of zinc anodes hinder their practical application. Here, we propose the extended substrate screening strategy for stabilizing zinc anodes and verify its availability (dsubstrate: dZn(002) = 1: 1→dsubstrate: dZn(002)=n:1, n = 1, 2). From a series of calculated phyllosilicates satisfying dsubstrate ≈ 2dZn(002), we select vermiculite, which has the lowest lattice mismatch (0.38%) reported so far, as the model to confirm the effectiveness of “2dZn(002)” substrates for zinc anodes protection. Then, we develop a monolayer porous vermiculite through a large-scale and green preparation as a functional coating for zinc electrodes. Unique “planting Zn(002) seeds” mechanism for “2dZn(002)” substrates is revealed to induce the oriented growth of zinc deposits. Additionally, the coating effectively inhibits side reactions and promotes zinc ion transport. Consequently, the modified symmetric cells operate stably for over 300 h at a high current density of 50 mA cm−2. This work extends the substrate screening strategy and advances the understanding of zinc nucleation mechanism, paving the way for realizing high-rate and stable zinc-metal batteries.

Toward Simultaneous Dense Zinc Deposition and Broken Side-Reaction Loops in the Zn//V2 O5 System.

The Zn//V2 O5 system not only faces the incontrollable growth of zinc (Zn) dendrites, but also withstands the cross-talk effect of by-products produced from the cathode side to the Zn anode, inducing interelectrode talk and aggravating battery failure. To tackle these issues, we construct a rapid Zn2+ -conducting hydrogel electrolyte (R-ZSO) to achieve Zn deposition modulation and side reaction inhibition in Zn//V2 O5 full cells. The polymer matrix and BN exhibit a robust anchoring effect on SO4 2- , accelerating Zn2+ migration and enabling dense Zn deposition behavior. Therefore, the Zn//Zn symmetric cells based on the R-ZSO electrolyte can operate stably for more than 1500 h, which is six times higher than that of cells employing the blank electrolyte. More importantly, the R-ZSO hydrogel electrolyte effectively decouples the cross-talk effects, thus breaking the infinite loop of side reactions. As a result, the Zn//V2 O5 cells using this modified hydrogel electrolyte demonstrate stable operation over 1,000 cycles, with a capacity loss rate of only 0.028 % per cycle. Our study provides a promising gel chemistry, which offers a valuable guide for the construction of high-performance and multifunctional aqueous Zn-ion batteries.

Toward Simultaneous Dense Zinc Deposition and Broken Side‐Reaction Loops in the Zn//V2O5 System

AbstractThe Zn//V2O5 system not only faces the incontrollable growth of zinc (Zn) dendrites, but also withstands the cross‐talk effect of by‐products produced from the cathode side to the Zn anode, inducing interelectrode talk and aggravating battery failure. To tackle these issues, we construct a rapid Zn2+‐conducting hydrogel electrolyte (R‐ZSO) to achieve Zn deposition modulation and side reaction inhibition in Zn//V2O5 full cells. The polymer matrix and BN exhibit a robust anchoring effect on SO42−, accelerating Zn2+ migration and enabling dense Zn deposition behavior. Therefore, the Zn//Zn symmetric cells based on the R‐ZSO electrolyte can operate stably for more than 1500 h, which is six times higher than that of cells employing the blank electrolyte. More importantly, the R‐ZSO hydrogel electrolyte effectively decouples the cross‐talk effects, thus breaking the infinite loop of side reactions. As a result, the Zn//V2O5 cells using this modified hydrogel electrolyte demonstrate stable operation over 1,000 cycles, with a capacity loss rate of only 0.028 % per cycle. Our study provides a promising gel chemistry, which offers a valuable guide for the construction of high‐performance and multifunctional aqueous Zn‐ion batteries.