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Rechargeable aqueous Zn metal batteries (RAZMBs) are considered as a competitive alternative to the next generation of energy storage system. However, the Zn stripping/plating reversibility is greatly limited by the dendrite growth and the side reactions on Zn anode. In virtue of the excellent protection and ion migration regulation effects, porous organic polymer artificial solid electrolyte interphases (POPASEIs) have attracted widespread attention in stabilizing Zn anode. This article summarizes the progress of Zn anode POPASEIs in recent years, divided into two categories according to the polymer matrix: porous polymer‐based POPASEIs and nonporous polymer‐based POPASEIs. The porous polymer‐based POPASEIs can be divided into porous coordination organic polymer (PCOOP)‐based and porous covalent organic polymers (PCVOP)‐based ASEIs according to the chemical structure, while nonporous polymer‐based POPASEIs can be divided into four types according to the pore‐forming strategies, including phase separation‐induced POPASEIs, template‐assisted POPASEIs, fiber‐formed POPASEIs, porous filler‐modified POPASEIs. In addition, the structural advantages, challenges, and perspectives of POPASEIs for Zn anode are also discussed to provide guidance for the further research and development of Zn anode ASEIs. [ABSTRACT FROM AUTHOR]

The practical application of Zn metal anodes is currently hindered by uncontrolled dendritic growth and water‐induced parasitic reactions that are closely related to the solvation structure and interfacial transport kinetics of Zn2+. Herein, a facile interface self‐gelation strategy is proposed to stabilize Zn anode by introducing ‐OH‐rich silica aerogel (HSA) on Zn anode surface. The unique interconnected network structure and strong hydrophilia of HSA made the aqueous electrolyte near Zn anode gel rapidly and spontaneously, resulting in the formation of a water‐poor gel interface layer. The interface layer can effectively accelerate the desolvation process and reduce water molecule activity near anode surface through hydrogen bonding interaction, thus achieving rapid Zn migration kinetics and alleviating side reactions. In addition, the well‐defined aerogel nanochannels can provide a fast Zn2+ migration path and homogenize Zn2+ flux, enabling rapid and uniform Zn deposition. As a result, the HSA‐modified Zn (HSA@Zn) anode exhibits excellent long‐term cycling stability (over 6000 h at 4 mA cm−2), and the feasibility for practical application of this HSA@Zn anode is further demonstrate in full cells. The aerogel‐driven interface self‐gelation strategy propose in this work provides new insights into the design of advanced Zn anode for aqueous zinc‐ion batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] Zinc metal anodes in aqueous electrolytes commonly face challenges such as dendrite growth and undesirable side reactions, limiting their application in the field of aqueous zinc-ion batteries (AZIBs) for energy storage. Drawing inspiration from industrial practices involving molybdenum salt solutions for metal modification, a polyoxometalate solution was formulated as a passivation solution for zinc anodes (referred to as MO solution). The formed passivation layer, referred to as the MO layer, exhibited a uniform and protective nature with a thickness of approximately 10 μm. The experimental results demonstrated that this passivation layer effectively suppressed side reactions at the zinc anode interface, as evidenced by lower corrosion current density for MO-Zn anodes. Additionally, the newly plated Zn was uniformly deposited atop the MO layer, ensuring coating integrity and inhibiting dendrite growth. As a result, under more demanding conditions such as a larger current of 8 mA cm−2, the MO-Zn anode displayed an extended cycle life exceeding 420 h in a symmetric battery, with an overpotential as low as 98 mV. This performance significantly outperformed that of commercially available pure Zn foils (with a cycle life of 60 h and an overpotential of 192 mV). Notably, a self-made Na-doped V 2 O 5 served as the cathode (referred to as NaVO), forming the MO-Zn//NaVO full battery. Even under high current test conditions of 2 A/g, the specific capacity of the MO-Zn//NaVO full battery remained substantial at 152.83 mAh/g after 1000 cycles. Furthermore, pouch batteries assembled with NaVO//MO-Zn successfully illuminated small bulbs. This study offers a viable optimization strategy for AZIB anodes and demonstrates the potential of using polyoxometalate solution for etching zinc anodes to inhibit dendrite growth and interfacial corrosion of zinc metal anodes. [ABSTRACT FROM AUTHOR]

The inevitable shuttling and slow redox kinetics of lithium polysulfides (LiPSs) as well as the uncontrolled growth of Li dendrites have strongly limited the practical applications of lithium‐sulfur batteries (LSBs). To address these issues, we have innovatively constructed the carbon nanotubes (CNTs) encapsulated Co nanoparticles in situ grown on TiN‐MXene nanosheets, denoted as TiN‐MXene‐Co@CNTs, which could serve simultaneously as both sulfur/Li host to kill "three birds with one stone" to (1) efficiently capture soluble LiPSs and expedite their redox conversion, (2) accelerate nucleation/decomposition of solid Li2S, and (3) induce homogeneous Li deposition. Benefiting from the synergistic effects, the TiN‐MXene‐Co@CNTs/S cathode with a sulfur loading of 2.5 mg cm−2 could show a high reversible specific capacity of 1129.1 mAh g−1 after 100 cycles at 0.1 C, and ultralong cycle life over 1000 cycles at 1.0 C. More importantly, it even achieves a high areal capacity of 6.3 mAh cm−2 after 50 cycles under a sulfur loading as high as 8.9 mg cm−2 and a low E/S ratio of 5.0 μL mg−1. Besides, TiN‐MXene‐Co@CNTs as Li host could deliver a stable Li plating/striping behavior over 1000 h. [ABSTRACT FROM AUTHOR]

The isotropy is a fundamental requirement for solving partial differential equations by the finite difference scheme. In this work, we first introduce the concept of the virtual nodes to construct the finite difference scheme, and propose several stencils of finite difference discretization to optimize the isotropy of the gradient and Laplacian operators. The isotropic error of the optimized gradient stencil is reduced to 4.1% and 7.5% of the conventional scheme and the typical 4th-order isotropic stencil that is widely used in the multiphase lattice Boltzmann method, while the optimized Laplacian stencil displays the best performance in the Fourier analysis. Then, the optimized stencils are applied to suppress the spurious currents in the multiphase lattice Boltzmann method. The spurious current is reduced to only 7.2% of that calculated by the typical 4th-order isotropic stencil at the reduced temperature 0.6, at which the liquid/gas density ratio is near to 1000. Furthermore, they are adopted to rectify the dendrite directions in the alloy solidification simulations by the phase field method. The angle deviation of dendrite growth is reduced to 15.7% of the conventional scheme. [ABSTRACT FROM AUTHOR]

Polymer coatings are emerged as promising candidates for zinc anode artificial solid electrolyte interphase (ASEI) owing to their barrier effect and zincophilicity. However, the poor ionic conductivity of conventional polymer coatings limits their application. Herein, inspired by epidermis function, a porous poly(methylmethacrylate) (PMMA) coating is fabricated to stabilize Zn anode via a novel phase inversion method. The modified Zn anode delivers a remarkable lifespan of over 4000 h at 1 mA cm−2, 1 mAh cm−2, and 120 h at 20 mA cm−2, 20 mAh cm−2 in symmetrical cells. Moreover, porous PMMA‐Zn||NVO full cell also exhibits an excellent cycling stability over 500 cycles at 1 A g−1 as well as an ultralong lifespan exceeding 5000 cycles at 5 A g−1. The excellent cycling stability and rate performance are mainly attributed to the avoided side reactions by the coating protection, as well as the enhanced diffusion and reaction kinetics derived from the good zincophilicity and porous structure of porous PMMA. The facile and universal method for fabricating porous polymer ASEI provides a new insight for the application of conventional polymer materials in Zn anode protection. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Display omitted] • Tween 80 additive modifies the solvation structure of Zn2+ ions. • Tween 80 additive reconstructs the hydrogen bond network in ZnSO 4 electrolyte. • Zn2+ ions complexed with Tween-80 create a protective hydrophobic layer. • Dual-layer Tween-80 on Zn anode prevents corrosion, reduces hydrogen evolution. Zinc metal anodes encounter significant challenges, including dendrite growth, hydrogen evolution, and corrosion, all of which impede the rate capability and longevity of aqueous zinc-ion batteries (AZIBs). To effectively tackle these issues, we introduced Tween-80 into the traditional ZnSO 4 electrolyte as an additive. Tween-80 possesses electronegative oxygen atoms that enable it to adsorb onto the zinc (Zn) anode surface, facilitating the directional deposition of Zn metal along the (0 0 2) orientation. The hydroxyl and ether groups within Tween-80 can displace some of the coordinated water molecules in the Zn2+ inner solvation shell. This disruption of the hydrogen bond network regulates the solvation structure of Zn2+ ions and suppresses the possibility of hydrogen evolution. Moreover, the long hydrocarbon chain present in Tween-80 exhibits excellent hydrophobic properties, aiding in the resistance against corrosion of the Zn anode by water molecules and reducing hydrogen evolution. Consequently, a symmetric cell equipped with the Tween-80 additive can cycle stably for over 4000 h at 1 mA cm−2 and 1 mA h cm−2. When paired with the V 2 O 5 cathode, the full cell demonstrates a high-capacity retention rate exceeding 80 % over 1000 cycles at a current density of 2 A g−1. This study underscores the advantages of utilizing non-ionic surfactants for achieving high-performance aqueous zinc-ion batteries. [ABSTRACT FROM AUTHOR]

Electrolyte additive engineering is a crucial method for enhancing the performance of aqueous zinc—ion batteries (AZIBs). Recently, most research predominantly focuses on the role of functional groups in regulating electrolytes, often overlooking the impact of molecule stereoscopic configuration. Herein, two isomeric sugar alcohols, mannitol and sorbitol, are employed as electrolyte additives to investigate the impact of the stereoscopic configuration of additives on the ZnSO4 electrolyte. Experimental analysis and theoretical calculations reveal that the primary factor for improving Zn anode performance is the regulation of the solvation sheath by these additives. Among the isomers, mannitol exhibits stronger binding energies with Zn2+ ions and water molecules due to its more suitable stereoscopic configuration. These enhanced bindings allow mannitol to coordinate with Zn2+, contributing to solvation structure formation and reducing the active H2O molecules in the bulk electrolyte, resulting in suppressed parasitic reactions and inhibited dendritic growth. As a result, the zinc electrodes in mannitol—modified electrolyte exhibit excellent cycling stability of 1600 h at 1 mA cm−2 and 900 h at 10 mA cm−2, respectively. Hence, this study provides novel insights into the importance of suitable stereoscopic molecule configurations in the design of electrolyte additives for highly reversible and high—rate Zn anodes. [ABSTRACT FROM AUTHOR]

Zn anodes in aqueous zinc‐ion batteries chronically suffer from pernicious side reactions and ineluctable dendrite growth, resulting in inadequate reversibility and suboptimal Coulombic efficiency (CE) and impeding commercialization. Herein, a multifunctional metal–organic coordination polymer layer (FAZ) is constructed on the zinc anode surface (FAZ@Zn) utilizing a simple self‐assembly strategy. The zincophilic FAZ interfacial layer with a high Zn2+ transfer number and low nucleation barrier effectively facilitates the de‐solvation process, supports the rapid transport of zinc ions, and contributes to the preferential growth of Zn (002) crystal planes, enabling dendrite‐free Zn deposition. Furthermore, the FAZ layer, as an interfacial pH regulating layer, effectively inhibits the direct contact between Zn and active water molecules, lowering the severity of side reactions. Consequently, the FAZ@Zn anode furnishes an eminent cycle stability over 6900 h, with a low polarization voltage at 1 mA cm−2 and 1 mA h cm−2 and a boosted CE of 99.88% over 4100 cycles. More encouragingly, when coupled with Na2V6O16·3H2O, the FAZ@Zn anode enables the full cell to deliver satisfactory rate performance and a 97% capacity retention over 1600 cycles. This work provides a simple strategy for the effective preparation of highly reversible zinc anodes for high‐performance aqueous zinc‐ion batteries. [ABSTRACT FROM AUTHOR]

Dendrite growth and other side‐reaction problems of zinc anodes in aqueous zinc‐ion batteries heavily affect their cycling lifespan and Coulombic efficiency, which can be effectively alleviated by the application of polymer‐based functional protection layer on the anode. However, the utilization rate of functional groups is difficult to improve without destroying the polymer chain. Here, a simple and well‐established strategy is proposed by controlling the orientation of functional groups (─SO3H) to assist the optimization of zinc anodes. Depending on the electrostatic effect, the surface‐enriched ─SO3H groups increase the ionic conductivity and homogenize the Zn2+ flux while inhibiting anionic permeation. This approach avoids the destruction of the polymer backbone by over‐sulfonation and amplifies the effect of functional groups. Therefore, the modified sulfonated polyether ether ketone (H‐SPEEK) coating‐optimized zinc anode is capable of longtime stable zinc plating/stripping, and moreover an enhanced cycling steadiness under high current densities is also detected in a series of Zn batteries with different cathode materials, which achieved by the inclusion of H‐SPEEK coating without causing any harmful effects on the electrolyte and cathode. This work provides an easy and efficient approach to further optimize the plating/stripping of cations on metal electrodes, and sheds lights on the scale‐up of high‐performance aqueous zinc‐ion battery technology. [ABSTRACT FROM AUTHOR]

A dual-functional ionic liquid additive, 1-butyl-3-methylimidazolium hydrogen sulfate (BMIHSO 4), is developed to tune the preferential Zn(002) crystallographic texture and simultaneously suppress the hydroxide sulfate accumulation on Zn anode by dynamically manipulating electrolyte pH-surroundings. The effective suppression of Zn dendrite growth enables a Zn symmetrical cell cycling stably to over one year. [Display omitted] Zn anodes suffer from the formation of uncontrolled dendrites aggravated by the uneven electric field and the insulating by-product accumulation in aqueous zinc-ion batteries (AZIBs). Here, an effective strategy implemented by 1-butyl-3-methylimidazolium hydrogen sulfate (BMIHSO 4) additive is proposed to synergistically tune the crystallographic orientation of zinc deposition and suppress the formation of zinc hydroxide sulfate for enhancing the reversibility on Zn anode surface. As a competing cation, BMI+ is proved to preferably adsorb on Zn-electrode compared with H 2 O molecules, which shields the "tip effect" and inhibits the Zn-deposition agglomerations to inducing the horizontal growth along Zn (002) crystallographic texture. Simultaneously, the protonated BMIHSO 4 additives could remove the detrimental OH– in real-time to fundamentally eliminate the accumulation of 6Zn(OH) 2 ·ZnSO 4 ·4H 2 O and Zn 4 SO 4 (OH) 6 ·H 2 O on Zn anode surface. Consequently, Zn anode exhibits an ultra-long cycling stability of one year (8762 h) at 0.2 mA cm−2/0.2 mAh cm−2, 3600 h at 2 mA cm−2/2 mAh cm−2 with a high plating cumulative capacity of 3.6 Ah cm−2, and a high average Coulombic efficiency of 99.6 % throughout 1000 cycles. This work of regulating Zn deposition texture combined with eliminating notorious by-products could offer a desirable way for stabilizing the Zn-anode/electrolyte interface in AZIBs. [ABSTRACT FROM AUTHOR]

Although metal–sulfur batteries (M–S batteries, M = Li, Na, K) are promising next‐generation energy‐storage devices because of ultrahigh theoretical energy density, low cost, and environmentally friendliness, their practical applications are significantly hindered by the shuttle effect of polysulfides and growth of alkali metal dendrites. These issues can be mitigated by using Janus metal atomic‐site catalysts, which possess the maximum atom utilization efficiency (≈100%), adjustable electronic structures, and tailorable catalytic sites, thereby effectively improving the electrochemical performance of M–S batteries. In this review, the recent progress and development of Janus metal atomic‐sites on the properties, synthesis, and characterizations are reviewed. Then, the recent advances in Janus metal atomic‐site catalysts intended for accelerating polysulfide conversion and regulating alkali metal deposition, briefly introducing the working principles of the Janus metal atomic‐site catalysts in M–S batteries, are systematically summarized. Furthermore, a high emphasis is placed on effective regulation strategies for the rational design of Janus metal atomic‐site catalysts in M–S batteries. Finally, the current challenges and future research directions are also presented to develop high‐efficiency Janus metal atomic‐site catalysts for high‐energy M–S batteries. [ABSTRACT FROM AUTHOR]

Uncontrolled dendrite growth and electrolyte‐induced intricate parasitic reactions are two great challenges that hinder the commercial applications of aqueous zinc‐ion batteries. Herein, a synchronous modulation strategy for Zn2+ interfacial migration behavior and electrolyte microenvironment is proposed by constructing a functional lanthanum hydroxide aerogel (LAG) interface layer on Zn anode surface. The in situ derivation of ion‐conducting zinc hydroxide sulfate (ZHS) from LAG layer results in the spontaneous generation of a hierarchic interface layer during the plating process, where the high Zn2+ selectivity of the upper dense ZHS layer can limit SO42− migration and allow for fast Zn2+ interfacial migration kinetics, while the aerogel layer with well‐defined nanochannels near the anode side can homogenize Zn2+ distribution, thus leading to the effective suppression of both dendrites and side reactions. Additionally, the pH microenvironment of the acidic electrolyte can be synchronously regulated by slightly soluble La(OH)3 aerogel, further inhibiting electrolyte corrosion and HER. Consequently, the modified Zn anode delivers highly reversible Zn plating/stripping and low‐voltage hysteresis, and the high areal‐capacity Zn||MnO2 full cells demonstrate considerable electrochemical performances under high Zn utilization conditions. This functional aerogel‐driven synchronous modulation strategy of Zn2+ migration behavior and electrolyte microenvironment provides new insight for stabilizing Zn metal anodes. [ABSTRACT FROM AUTHOR]

Ammonium chloride (NH4Cl) has been extensively studied as a transparent analogue for investigating the solidification of metals due to its distinctive properties and the simplicity of the experimentation. Furthermore, NH4Cl exhibits a striking resemblance in solidification behavior to the majority of binary eutectic alloy systems, rendering it a valuable model for studying phase transition phenomena. Experiments conducted on ammonium chloride are frequently employed to validate numerical models for predicting grain structures, macrosegregation, and the columnar-to-equiaxed transition (CET). This latter phenomenon arises due to differences in the velocities of columnar dendrite tips and the liquidus isosurface. However, the kinetics of dendrite tip growth, as a function of supersaturation, remains poorly understood for this commonly used alloy. The objective of this study was to utilize the available experimental data in conjunction with Ivantsov correlations to shed light on the ambiguous kinetics. The results indicate that when considering the crystal–melt density ratio, the Ivantsov solution offers a good correlation. Furthermore, incorporating a moderate interfacial kinetic coefficient enhances the correlations further. This correlation can be implemented in numerical models, which will aid in the determination of the columnar front, the columnar-to-equiaxed transition, and the equiaxed growth velocities. [ABSTRACT FROM AUTHOR]

Effective therapies to treat skin hypopigmentation disorders caused by diminished melanin synthesis or export are limited due to potential side effects. In this work, we explored if cyclocurcumin (CYC), a curcuminoid found in minor amounts in turmeric rhizomes, might enhance the process of melanogenesis. CYC did not demonstrate antioxidant activity as evaluated by the DPPH assay. At noncytotoxic concentrations, CYC robustly enhanced melanin synthesis and melanin export in B16F10 mouse melanoma cells, which was correlated to increased cellular tyrosinase activity. The melanogenesis-stimulating efficacy of CYC was enhanced in B16F10 cocultures with HaCaT cells. Next, our results in MNT-1 human melanoma cells confirmed that CYC is a stimulator of both melanin synthesis and melanin export and acts by upregulating microphthalmia transcription factor (MITF) protein, although CYC did not alter tyrosinase protein or tyrosinase activity in MNT-1 cells. Moreover, the examination of CYC in MNT-1:HaCaT cocultures continued to show a more potent effect on stimulating melanin synthesis, as well as its export to recipient keratinocytes. Finally, CYC was shown to demonstrate a potent capacity to stimulate melanin production in primary human melanocytes from a Caucasian donor (HEMn-LP cells), although the effects on cellular tyrosinase activity were biphasic. Taken together, this is the first study to report the novel finding that CYC is a potent promelanogenic candidate that exhibits potential utility in the therapeutic management of skin disorders arising due to hypopigmentation in humans. Future studies that examine the molecular mechanisms and elucidate the promelanogenic efficacy of CYC in vivo are necessary. [ABSTRACT FROM AUTHOR]

Aqueous Zn‐ion batteries with mild acidic electrolytes are considered the promising energy storage solutions due to their outstanding merits of high energy density and cost‐effectiveness. However, the rampant dendrite growth and severe parasitic reactions caused by a series of factors such as irregular Zn2+ transport pathway and pH variation would result in poor cycling stability. Herein, a self‐regulated interface strategy implemented by ammonium persulfate ((NH4)2S2O8, denoted as APS) multifunctional additive is proposed to simultaneously address the above issues. The zincophilic NH4+ preferentially adsorbs on the Zn protuberance to exclude water molecules and shield the "tip effect," thus inhibiting side‐reactions and inducing uniform Zn deposition. Moreover, NH4+ and S2O82− can dynamically adjust H+ and OH− concentrations in a pH self‐buffer manner, thus effectively mitigating hydrogen evolution reaction and formation of by‐products. Consequently, with the existence of APS additive, Zn anode exhibits ultrahigh coulombic efficiency (CE) of 99.9% over 9000 cycles and ultra‐long lifespan of 4300 h at 5 mA cm−2. Furthermore, even under high NH4V4O10 mass loading (9.4 mg cm−2) and thin zinc foil (10 µm), the assembled NH4V4O10//Zn pouch cell with APS additive can still maintain stably over 210 cycles, demonstrating its excellent value for application. [ABSTRACT FROM AUTHOR]

A lattice Boltzmann model (LBM) with sharp interface tracking is developed to simulate the motion and growth of dendrites in non-equilibrium solidification of alloys. The model is validated through comparative analysis with the drafting-kissing-tumbling (DKT) phenomena of two and three particles and the continuous growth model (CGM), and demonstrates its computational efficiency advantage without compromising accuracy by comparison with the multi-phase field (MPF) model. Subsequently, the model is utilized to investigate the dendrite morphology transition and primary dendritic arm spacing (PDAS). It is found that the velocity dependent solute partition and the resulting changes in constitutional undercooling strongly influence the estimated morphology region and PDAS. Moreover, the segregation and microstructure evolution during the rapid solidification were studied. And the results revealed that free dendrites lead to significant changes in microstructure and segregation under the influence of non-equilibrium effects. This work illustrates the great potential of the proposed model in simulating dendrites and microstructure evolution under a wide range of solidification conditions. Its suitability for extreme conditions and non-equilibrium solidification can contribute to the understanding of microstructure formation patterns and solute segregation in rapid solidification.

With increasing turbine inlet temperatures in aero-engines, the demand for temperature-resistant turbine blades has led to the widespread use of nickel-based single crystal superalloys. These alloys, known for their exceptional performance in high-temperature and high-stress environments, incorporate advanced cooling structures like lamilloy and double wall cooling to enhance temperature tolerance. As the development of aviation technology, thin-walled structures are widely used in turbine blades of aero-engines. However, the adoption of ultra-thin wall structures, particularly in lamilloy turbine blades with thicknesses of 0.5 mm or less, presents a significant manufacturing challenge and will cause the degradation of mechanical properties. This study delves into the growth and evolution of dendrites in the nickel-based single-crystal superalloy DD403, exploring thin-walled specimens with varying thicknesses during directional solidification. Findings reveal that decreasing wall thickness correlates with a reduction in average primary dendrite arm spacing, smaller γ′ precipitates sizes within the dendrite core and interdendritic regions, and reduced microsegregation levels of Al, Ti, Co and W. These insights contribute to optimizing thin-walled turbine blade performance in aero-engines applications.

Severe dendrite growth on Zn anodes poses a significant challenge to the development of Zn‐based batteries. An effective strategy for inhibiting the formation of Zn dendrites involves electrode modification. In this study, hollow nitrogen‐doped carbon spheres (HNCS) are synthesized and used as electrodes to regulate Zn deposition in Zn‐based flow batteries. The electrochemical performance of HNCS reveals that the pyrrole nitrogen of HNCS changes the electrode surface state. Therefore, HNCS can inhibit the hydrogen evolution reaction and achieve uniform Zn deposition. HNCS can effectively inhibit dendrite growth and improve the reversibility of the Zn plating/stripping process to regulate the reversibility of Zn‐based batteries. The zinc‐bromine redox flow battery assembled with HNCS significantly reduces the hydrogen evolution reaction and exhibits a coulombic efficiency of 90 % and energy efficiency of 73 % at a current density of 60 mA cm−2. Similarly, an alkaline zinc‐iron flow battery can maintain high Coulombic efficiency and energy efficiency of 83 %. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

During the establishment of neuronal circuits, axons and dendrites grow and branch to establish specific synaptic connections. This complex process is highly regulated by positive and negative extracellular cues guiding the axons and dendrites. Our group was pioneer in describing that one of these signals are the extracellular purines. We found that extracellular ATP, through its selective ionotropic P2X7 receptor (P2X7R), negatively regulates axonal growth and branching. Here, we evaluate if other purinergic compounds, such as the diadenosine pentaphosphate (Ap5A), may module the dynamics of dendritic or axonal growth and branching in cultured hippocampal neurons. Our results show that Ap5A negatively modulates the dendrite's growth and number by inducing transient intracellular calcium increases in the dendrites' growth cone. Interestingly, phenol red, commonly used as a pH indicator in culture media, also blocks the P2X1 receptors, avoided the negative modulation of Ap5A on dendrites. Subsequent pharmacological studies using a battery of selective P2X1R antagonists confirmed the involvement of this subunit. In agreement with pharmacological studies, P2X1R overexpression caused a similar reduction in dendritic length and number as that induced by Ap5A. This effect was reverted when neurons were co-transfected with the vector expressing the interference RNA for P2X1R. Despite small hairpin RNAs reverting the reduction in the number of dendrites caused by Ap5A, it did not avoid the dendritic length decrease induced by the polyphosphate, suggesting, therefore, the involvement of a heteromeric P2X receptor. Our results are indicating that Ap5A exerts a negative influence on dendritic growth. [ABSTRACT FROM AUTHOR]

One key barrier to using lithium‐metal anode batteries is that metal dendrites can penetrate solid electrolytes, causing short‐circuits and battery failures. It is established that this failure is likely caused by crack propagation due to electrodeposition‐induced stresses from lithium metal. This study explores ways to harness these electrochemical‐mechanical couplings to control dendrite growth and improve battery reliability using a phase‐field model and targeted fracture experiments. The results show that dendrite growth can be effectively mitigated by applying mechanical stresses or tailoring the material's fracture toughness. This study also outlines the requirements for compressive stress to halt or deflect dendrites as a function of the overpotential and discusses the role of microstructure in this process. [ABSTRACT FROM AUTHOR]

Dendrite growth is a complex liquid-solid phase transition process involving multiple physical factors. A phase-field lattice-Boltzmann method was developed to simulate the two- and three-dimension dendrite growth of Al-Cu alloy. The effect of fully coupled thermal-solute-convection interaction on the dendrite growth was investigated by incorporating a parallel-adaptive mesh refinement algorithm into the numerical model. By accurately reproducing the latent heat release, solute diffusion and convective transport behaviors at the liquid-solid interface, the interaction mechanism among thermal-solute-convection transport as well as their coupling effects on the dendrite growth dynamics were discussed. The simulation results show that the release of latent heat slows down the dendrite growth rate, and both natural and forced convection disrupt the symmetrical growth of dendrites. Their combination makes the growth of dendrites more complex, capturing important physical aspects such as recalescence, dendrite tip splitting, dendrite tilting, dendrite remelting, and solute plume in the simulation case. Based on the robustness and powerful ability of the numerical model, the formation mechanisms of these physical aspects were revealed. [ABSTRACT FROM AUTHOR]

At present, the commercial application of Li─S cells is impeded by many challenging issues, especially the shuttle effect of dissolved lithium polysulfides (LiPSs) and severe dendritic growth. Applying a sole kind of host material owing dual functions, including inhibiting LiPSs dissolution/shuttling andguiding Li plating/stripping, has recently become a prospective solution. Currently, a systematic review of advanced dual‐functional electrodes aiming at the cathode and anode side simultaneously is scarce. Herein, this review points at such dual‐functional electrodes and summarizes the recent progress from the select host materials to designs. First, the rough challenges and ordinary solutions on the single side of the Li─S cell are illustrated. Then, the potentials of different materials to dual‐functional electrodes are discussed, such as carbon‐based materials, single‐atom catalysts (SACs), transition metal compounds (TMCs), heterostructure hybrids (HHs), and polymers. After that, the design methods for dual‐functional electrodes with high performance are explored and summarized by slurry‐coating and self‐supporting (electrospinning (ES), 3D printing (3DP), solvent method (SM), chemistry vapor deposition (CVD) and vacuum filtration (VF)). Besides, the possibility of applying the dual‐functional electrodes to other metal‐sulfur cells is discussed. Finally, design principles and prospects in dual‐functional electrodes for future research and commercial application are proposed as guidelines. [ABSTRACT FROM AUTHOR]

The control of the solidification structure of a casting billet is directly correlated with the quality of steel. Variations in superheat can influence the transition from columnar crystals to equiaxed crystals during the solidification process, subsequently impacting the final solidification structure of the billet. In this study, a model of microstructure evolution during billet solidification was established by combining simulation and experiment, and the dendrite growth microstructure evolution during billet solidification under different superheat was studied. The results show that when the superheat is 60 K, the complete solidification time of the casting billet from the end of the 50 mm section is 252 s, when the superheat is 40 K, the complete solidification time of the casting billet is 250 s, and when the superheat is 20 K, the complete solidification time of the casting billet is 245 s. When the superheat is 20 K, the proportion of the equiaxed crystal region is higher—the highest value is 53.35%—and the average grain radius is 0.84556 mm. The proportion of the equiaxed crystal region decreases with the increase of superheat. When the superheat is 60 K, the proportion of the equiaxed crystal region is the lowest—the lowest value is 46.27%—and the average grain radius is 1.07653 mm. Proper reduction of superheat can obviously reduce the size of equiaxed crystal, expand the area of equiaxed crystal and improve the quality of casting billet. [ABSTRACT FROM AUTHOR]

Abstract Dendrite growth and other side‐reaction problems of zinc anodes in aqueous zinc‐ion batteries heavily affect their cycling lifespan and Coulombic efficiency, which can be effectively alleviated by the application of polymer‐based functional protection layer on the anode. However, the utilization rate of functional groups is difficult to improve without destroying the polymer chain. Here, a simple and well‐established strategy is proposed by controlling the orientation of functional groups (─SO3H) to assist the optimization of zinc anodes. Depending on the electrostatic effect, the surface‐enriched ─SO3H groups increase the ionic conductivity and homogenize the Zn2+ flux while inhibiting anionic permeation. This approach avoids the destruction of the polymer backbone by over‐sulfonation and amplifies the effect of functional groups. Therefore, the modified sulfonated polyether ether ketone (H‐SPEEK) coating‐optimized zinc anode is capable of longtime stable zinc plating/stripping, and moreover an enhanced cycling steadiness under high current densities is also detected in a series of Zn batteries with different cathode materials, which achieved by the inclusion of H‐SPEEK coating without causing any harmful effects on the electrolyte and cathode. This work provides an easy and efficient approach to further optimize the plating/stripping of cations on metal electrodes, and sheds lights on the scale‐up of high‐performance aqueous zinc‐ion battery technology.

The rapid solidification speed and significant temperature gradient observed in the wire and arc additive manufacturing (WAAM) process result in a deviation of the solid-liquid interface from the equilibrium state assumed by the conventional directional solidification phase field (PF) model. This, in turn, limits the ability of the traditional directional solidification PF model to accurately depict the microstructure evolution in additive manufacturing, where non-equilibrium effects dominate. In this work, we employed a 3D finite element (FE) model to simulate the temperature distribution during the wire and arc additive manufacturing (WAAM) process. Additionally, a modified PF model that applies to additive manufacturing is also used to simulate the dendrite morphology and solute segregation behavior in the WAAM process at different scanning speeds. Experimental validation of the simulation results was also conducted. We observed a significant reduction in dendrite growth velocity and solute segregation with increasing scanning speed, attributable to the combined effects of the temperature gradient G(t) and solidification speed Vp. Furthermore, higher scanning speeds were found to increase the primary dendrite arm spacing (PDAS) and average dendrite width. Importantly, our results demonstrated a quantitative agreement between the simulation results using the modified directional solidification PF model and the experimental observations. This approach provides a foundation for selecting and predicting processing parameters and microstructural characteristics under additive manufacturing conditions, facilitating a comprehensive analysis of dendrite growth and solute segregation at different scanning speeds in the WAAM process.

Zn‐metal anode for Zn ion battery (ZIB) suffers from multiple catastrophic issues (severe corrosion reaction, concomitant hydrogen evolution, and dendrite growth) that are always intricate and are inevitably interactional, setting up critical obstacle for application of ZIB. Herein, a multifunctional sieve (MS) consisting of inorganic nanolayers and organic molecule layers is proposed to solve these issues synchronously based on its trifunctional roles (accelerating Zn2+, repelling H2O, and binding OH). As a prototype, porous nano‐architecture MS composed of steric acid molecule layer and TiO2 nanosheets (derived from MXene) (SA@TiO2‐MS) is deliberately created on the surface of zinc anodes (Zn@SA@TiO2‐MS) employing in situ self‐assembly strategy. Theoretical calculations together with proof‐of‐experiment prove that SA@TiO2‐MS can alleviate the growth of Zn dendrites, mitigate hydrogen evolution, relieve corrosion reaction, via the acceleration of the Zn2+ diffusion, the repelling of H2O with hydrophobic SA layer, as well as the bonding of OH with TiO2 layer. As a result, Zn@SA@TiO2‐MS||Zn@SA@TiO2‐MS symmetric cell achieves a lifespan up to 1100 h at 5 mA cm−2. In addition, the full‐cell by pairing carbon‐cloth@MnO2 with Zn@SA@TiO2‐MS delivered capacity retention of 70.3% after 2000 cycles. This work proposes fundamentally a more comprehensive approach to balance the issues faced by Zn‐metal anode. [ABSTRACT FROM AUTHOR]

The poor anode/electrolyte compatibility and dendrite growth have discouraged the development of solid‐state sodium‐metal batteries (SSSMBs). Here, a self‐formed interphase with a unique Fe valence gradient is designed to stabilize the anode interface of Na3Zr2Si2PO12 solid electrolyte. This interphase consists of a Fe‐ and NaF‐containing outer layer near the Na anode and a Fe2+/Fe3+‐rich inner layer, which are in situ formed upon contacting Na with a sodiophilic α‐Fe2O3‐xFx interlayer specially coated on Na3Zr2Si2PO12. The NaF and Fe prevents continuous reduction reactions and homogenize the electric filed, while the iron oxide gradient layer offers buffering Na storage during plating, further suppressing dendrite growth. Benefiting from the dynamically stable, low‐impedance and dendrite‐free interface, the symmetric cells achieve a 20‐fold reduction in interfacial resistance and a fourfold enhancement in critical current density (CCD) at 25 °C, and powered a high CCD of 1.9 mA cm‐2 and a 1000‐h cycle life at 1 mA cm‐2 at 80 °C. The corresponding SSSMBs based on Na3V2(PO4)3 cathodes deliver a capacity retention rate of 96% over 120 cycles at 1 C. This robust interface design supports one of the best electrochemical performances ever reported and offers a comprehensive solution to stabilize the Na3Zr2Si2PO12/Na interface toward practical SSSMBs. [ABSTRACT FROM AUTHOR]

Zinc‐bromine batteries (ZBBs) have recently gained significant attention as inexpensive and safer alternatives to potentially flammable lithium‐ion batteries. Zn metal is relatively stable in aqueous electrolytes, making ZBBs safer and easier to handle. However, Zn metal anodes are still affected by several issues, including dendrite growth, Zn dissolution, and the crossover of Br species from cathodes to corrode anodes, resulting in self‐discharge and fast performance fading. Similarly, Br2 undergoes sluggish redox reactions on cathodes, which brings several issues such as poor reaction kinetics, the highly corrosive nature of Br species leading to corrosion of separators and poisoning of anodes, and the volatile nature of Br species causing increased internal pressures, etc. These issues are compounded in flowless ZBB configuration as no fresh electrolyte is available to provide extra/fresh reaction species. In this review, the factors controlling the performance of ZBBs in flow and flowless configurations are thoroughly reviewed, along with the status of ZBBs in the commercial sector. The review also summarizes various novel methodologies to mitigate these challenges and presents research areas for future studies. In summary, this review will offer a perspective on the historical evolution, recent advancements, and prospects of ZBBs. [ABSTRACT FROM AUTHOR]

[Display omitted] Aqueous zinc-ion batteries (AZIBs) have caused significant research attention due to their low redox potential of 0.76 V, high theoretical capacity of 820 mAh g−1. However, the dendrite growth of zinc anode and the side reactions caused by water seriously affect the cycle life of AZIBs. To solve the above problems, a new method of etching zinc anodes with CuCl 2 salt solution was designed, which the zinc anode was named CZn. The process resulted to a uniformly distributed micro gully morphology on the zinc surface, and providing an increased number of nucleation sites for zinc deposition and reducing local current density. The calculation results of exchange current density and activation energy show that CZn has stronger Zn/Zn2+ kinetic effect. At a current density of 5 mA cm−2 and an area capacity of 5 mAh cm−2, cycle life of the CZn symmetrical cell can reach 500 h, which is more than seven times that of the raw Zn symmetrical cell. This work proposes a simple method of zinc anode protection, which provides a new idea for zinc metal anode protection. [ABSTRACT FROM AUTHOR]

[Display omitted] Hypothesis : Aqueous zinc-ion batteries (AZIBs) have received considerable attention owing to their safety, low cost, and environmental benignity. However, the side reactions of hydrogen evolution revolution and Zn dendrite growth reduce the Coulombic efficiency and life span of AZIBs. To address these issues, we designed an artificial protective layer of a Te-hybridized core–shell zeolitic imidazolate framework (ZIF). Experiments : A core–shell structure of ZIF-8@ZIF-67 was first developed as a protecting layer on the Zn anode. To improve the poor conductivity of ZIF and its affinity for Zn, the core–shell structure was hybridized with zincophilic Te to increase the surface area and reduce the charge-transfer resistance. Findings : By incorporating metallic Te into ZIF-8 and ZIF-67, the nucleation potential and charge-transfer resistance were significantly reduced, enhancing the ion reaction kinetics and electron migration. Benefiting from the Te-hybridized ZIF-8@ZIF-67-derived nitrogen-doped porous carbon (Te-hybridized ZIF-8@ZIF-67/NC) layer, a full cell of Zn coated with Te-hybridized ZIF-8@ZIF-67/NC//MnO 2 exhibited an excellent rate performance of 214 mAh g−1 at an ultrahigh current density of 10 A g−1 and ultralong cycle life (3200 cycles) without the formation of Zn dendrites. [ABSTRACT FROM AUTHOR]

As the application of next-generation energy storage systems continues to expand, rechargeable secondary batteries with enhanced energy density and safety are imperative for energy iteration. Sodium-ion batteries (SIBs) have attracted extensive attention and are recognized as ideal candidates for large-scale energy storage due to the abundant sodium resources and low cost. Sodium metal anodes (SMAs) have been considered as one of the most attractive anode materials for SIBs owing to their high specific capacity (1166 mAh g−1), low redox potential, and abundant natural resources. However, the uncontrollable dendrite growth and inevitable side reactions on SMA lead to the continuous deterioration of the electrochemical performance, causing serious safety concerns and limiting their practical application in the future. Therefore, the construction of stable dendrite-free SMAs is a pressing problem for advanced sodium metal batteries (SMBs). In this review, we comprehensively summarize the research progress in suppressing the formation of sodium dendrite, including artificial solid electrolyte interphase (SEI), liquid electrolyte modification, three-dimensional (3D) host materials, and solid-state electrolyte. Additionally, key aspects and prospects of future research directions for SMAs are highlighted. We hope that this timely review can provide an overall picture of sodium protection strategies and stimulate more research in the future.

Highlights The synergistic “anchor-capture” mechanism of polar groups on Zn stripping/plating process is firstly proposed. The amino group firmly anchors on Zn surface and the carboxyl group strongly captures Zn2+, constructing a robust anode–electrolyte interface and inducing uniform Zn deposition. The ultra-stable cycle lifespan of Zn–Zn symmetric cell (over 2800 h) and high utilization rate of Zn anode (the depth of discharge up to 68% for 200 h) are achieved under the proposal of synergistic “anchor-capture.”

Lithium (Li) metal is a potential anode material for high energy density batteries. However, issues such as lithium dendrite growth, interface instability, poor cycling stability and large volume expansion limit the application of lithium metal anode. Aiming at the problem of dendritic growth and volume expansion, a semi-confined hierarchical porous carbon (HPC) material with a large specific surface area was prepared by template method. The high specific area of HPC electrode can reduce the local current density of Li deposition, and the rich pore structure can restrict the Li deposition in it, thus inhibiting the dendritic growth and alleviating the volume expansion. Li‖HPC battery can cycle for more than 250 cycles at a current density of 1.0 mA/cm2 and a deposition capacity of 1.0 mAh/cm2, maintaining a Coulombic efficiency of 97.6%. Li@HPC‖lithium iron phosphate a deposition capacity of (LiFePO4) full cell has a specific capacity of 93.6 mAh/g after 100 cycles at 0.5 C, which is higher than that of Li@Cu‖LiFePO4 full cell (60.8 mAh/g) with an increase of by 32.8 mAh/g.

Electrolyte additive engineering is a crucial method for enhancing the performance of aqueous zinc—ion batteries (AZIBs). Recently, most research predominantly focuses on the role of functional groups in regulating electrolytes, often overlooking the impact of molecule stereoscopic configuration. Herein, two isomeric sugar alcohols, mannitol and sorbitol, are employed as electrolyte additives to investigate the impact of the stereoscopic configuration of additives on the ZnSO4 electrolyte. Experimental analysis and theoretical calculations reveal that the primary factor for improving Zn anode performance is the regulation of the solvation sheath by these additives. Among the isomers, mannitol exhibits stronger binding energies with Zn2+ ions and water molecules due to its more suitable stereoscopic configuration. These enhanced bindings allow mannitol to coordinate with Zn2+, contributing to solvation structure formation and reducing the active H2O molecules in the bulk electrolyte, resulting in suppressed parasitic reactions and inhibited dendritic growth. As a result, the zinc electrodes in mannitol—modified electrolyte exhibit excellent cycling stability of 1600 h at 1 mA cm−2 and 900 h at 10 mA cm−2, respectively. Hence, this study provides novel insights into the importance of suitable stereoscopic molecule configurations in the design of electrolyte additives for highly reversible and high—rate Zn anodes.

Ammonium chloride (NH4Cl) has been extensively studied as a transparent analogue for investigating the solidification of metals due to its distinctive properties and the simplicity of the experimentation. Furthermore, NH4Cl exhibits a striking resemblance in solidification behavior to the majority of binary eutectic alloy systems, rendering it a valuable model for studying phase transition phenomena. Experiments conducted on ammonium chloride are frequently employed to validate numerical models for predicting grain structures, macrosegregation, and the columnar-to-equiaxed transition (CET). This latter phenomenon arises due to differences in the velocities of columnar dendrite tips and the liquidus isosurface. However, the kinetics of dendrite tip growth, as a function of supersaturation, remains poorly understood for this commonly used alloy. The objective of this study was to utilize the available experimental data in conjunction with Ivantsov correlations to shed light on the ambiguous kinetics. The results indicate that when considering the crystal–melt density ratio, the Ivantsov solution offers a good correlation. Furthermore, incorporating a moderate interfacial kinetic coefficient enhances the correlations further. This correlation can be implemented in numerical models, which will aid in the determination of the columnar front, the columnar-to-equiaxed transition, and the equiaxed growth velocities.

Thermal and solute diffusion plays an important role in α-Mg dendrite growth, the diffusion mechanism of which is still unclear. Here, thermal and solute diffusion in α-Mg dendrite growth of Mg-5wt.%Zn alloy under non-isothermal solidification were studied using the phase-field method. Results show that solidification latent heat will be concentrated at the dendrite intersection, which makes thermal field distribution non-uniform, and it is similar to the profile formed by connecting primary dendrite tips. The increase in temperature will shorten primary dendrite arms, reduce side-branching development, increase dendrite tip temperature, and decrease dendrite tip concentration stability. Moreover, solidification latent heat will first diffuse to undercooled melt, then diffuse to other areas, finally, system temperature tends to be unified. The variation range of concentration difference is very small in the solidification process, and solute field distribution is uniform all the time. The local high-concentration areas will be formed after the superposition of the solute enrichment layer, and solute atoms will first diffuse to undercooled melt through the solid-liquid interface, and then concentrate between side-branching and dendrites.

Abstract Zinc‐bromine batteries (ZBBs) have recently gained significant attention as inexpensive and safer alternatives to potentially flammable lithium‐ion batteries. Zn metal is relatively stable in aqueous electrolytes, making ZBBs safer and easier to handle. However, Zn metal anodes are still affected by several issues, including dendrite growth, Zn dissolution, and the crossover of Br species from cathodes to corrode anodes, resulting in self‐discharge and fast performance fading. Similarly, Br2 undergoes sluggish redox reactions on cathodes, which brings several issues such as poor reaction kinetics, the highly corrosive nature of Br species leading to corrosion of separators and poisoning of anodes, and the volatile nature of Br species causing increased internal pressures, etc. These issues are compounded in flowless ZBB configuration as no fresh electrolyte is available to provide extra/fresh reaction species. In this review, the factors controlling the performance of ZBBs in flow and flowless configurations are thoroughly reviewed, along with the status of ZBBs in the commercial sector. The review also summarizes various novel methodologies to mitigate these challenges and presents research areas for future studies. In summary, this review will offer a perspective on the historical evolution, recent advancements, and prospects of ZBBs.

Abstract The reversibility of Zn plating/stripping during cycling is adversely affected by dendritic growth, electrochemical corrosion, surface passivation, and hydrogen generation on the Zn anodes for rechargeable aqueous zinc ion batteries (ZIBs). Herein, through an ordinary anodic etching process, a uniform porous ZnP matrix protective layer was created on the Zn foil (Zn@ZnP). The large and accessible specific surface area of the prepared Zn@ZnP can facilitate contact with the electrolyte, accelerating the migration and enhancing the desolvation of Zn2+, effectively enhancing the Zn deposition kinetics. According to studies from scanning electron microscopy (SEM) and multiscale optical microscopy, the Zn@ZnP electrode effectively inhibits the growth of dendrites with excellent Zn plating/stripping reversibility. In consequence, the symmetric cell with the Zn@ZnP electrodes displays a long‐term cycle life of over 1260 h at 10 mA cm−2. The full cell, consisting of Zn@ZnP anodes and MnO2‐based cathode, demonstrated a high discharge capacity of 145 mAh g−1 after cycling 500 times at the current density of 1000 mA g−1. A scalable method for designing a homogeneous anode protection layer enables dendrite‐free zinc metal anodes, paving the way for interface modification of other metal anodes.

K‐metal batteries have become one of the promising candidates for the large‐scale energy storage owing to the virtually inexhaustible and widely potassium resources. The uneven K+ deposition and dendrite growth on the anode causes the batteries prematurely failure to limit the further application. An integrated K‐metal anode is constructed by cold‐rolling K metal with a potassiphilic porous interconnected mediator. Based on the experimental results and theoretical calculations, it demonstrates that the potassiphilic porous interconnected mediator boosts the mass transportation of K‐metal anode by the K affinity enhancement, which decreases the concentration polarization and makes a dendrite‐free K‐metal anode interface. The interconnected porous structure mitigates the internal stress generated during repetitive deposition/stripping, enabling minimized the generation of electrode collapse. As a result, a durable K‐metal anode with excellent cycling ability of exceed 1, 000 h at 1 mA cm−2/1 mAh cm−2 and lower polarization voltage in carbonate electrolyte is obtained. This proposed integrated anode with fast K+ kinetics fabricated by a repeated cold rolling and folding process provides a new avenue for constructing a high‐performance dendrites‐free anode for K‐metal batteries. [ABSTRACT FROM AUTHOR]

Zn metal anode suffers from dendrite growth and side reactions during cycling, significantly deteriorating the lifespan of aqueous Zn metal batteries. Herein, we introduced an ultrathin and ultra‐flat Sb2O3 molecular crystal layer to stabilize Zn anode. The in situ optical and atomic force microscopes observations show that such a 10 nm Sb2O3 thin layer could ensure uniform under‐layer Zn deposition with suppressed tip growth effect, while the traditional WO3 layer undergoes an uncontrolled up‐layer Zn deposition. The superior regulation capability is attributed to the good electronic‐blocking ability and low Zn affinity of the molecular crystal layer, free of dangling bonds. Electrochemical tests exhibit Sb2O3 layer can significantly improve the cycle life of Zn anode from 72 h to 2800 h, in contrast to the 900 h of much thicker WO3 even in 100 nm. This research opens up the application of inorganic molecular crystals as the interfacial layer of Zn anode. [ABSTRACT FROM AUTHOR]

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The impact of four typical surface finishes on electrochemical migration in printed circuit board production was studied using a modified water drop test, and the electrochemical migration phenomena of each surface finish at different bias voltages were analyzed. Based on the analysis of the experimental results, the four surface finishes were ranked in terms of their ability to resist electrochemical migration, as follows: electroless nickel/immersion gold (ENIG) > lead-free hot air solder leveling (HASL) > HASL > Cu. For the lead-free HASL, HASL, and Cu surface finishes, the growth of dendrites was mainly related to the hydroxide solubility product of metal ions, with a smaller solubility product leading to a larger area of precipitates, which further hindered the emergence and growth of dendrites. The electrochemical migration process of ENIG differed from other surface finishes. Gold was not involved in the electrochemical migration process, and no typical cathodic dendrite growth phenomenon was observed. Only nickel hydroxide and oxide formed from the anode edge and migrated toward the cathode with low conductivity, resulting in high electrochemical migration resistance for the ENIG surface finish. [ABSTRACT FROM AUTHOR]

A primary melted mark (PMM) on copper wire has been expected to identify the fire origin. However, the solidification microstructure under various cooling conditions has not been extensively studied. In this research, the effects of cooling conditions on PMM microstructure before and after heat treatment were investigated. The results represent dendrite growth direction to the surface of the melted mark with copper dendrites surrounded by (Cu+Cu2O) eutectic structure for air and water-cooling specimens. Moreover, the melted mark cooled in the air has more than twice of secondary dendrite arm spacing (SDAS) than the water-cooling sample in the case of pre-heat treatment. After heat treatment and cooled down in the furnace, air, and water: the dendritic structure disappears and Cu2O precipitates on the copper matrix. The smaller crystallite size and oxide layer cracking could be found in a higher cooling rate case. Therefore, by connecting thermal history with solidification structure and surface oxidation morphology, the change in microstructures and physical parameters of PMM could be expected to be helpful for fire investigation. [ABSTRACT FROM AUTHOR]

The dendrite growth behavior of high-strength steel during slab continuous casting with a traveling-wave magnetic field was studied in this paper. The morphology of the solidification structure and composition distribution were analyzed. Results showed that the columnar crystals could deflect and break when the traveling-wave magnetic field had low current intensity. With the increase in current intensity, the secondary dendrite arm spacing and solute permeability decreased, and the columnar crystal transformed into an equiaxed crystal. The electromagnetic force caused by the traveling-wave magnetic field changed the temperature gradient and velocity magnitude and promoted the breaking and fusing of dendrites. Dendrite compactness and composition uniformity were arranged in descending order as follows: columnar-to-equiaxed transition (high current intensity), columnar crystal zone (low current intensity), columnar-to-equiaxed transition (low current intensity), and equiaxed crystal zone (high current intensity). Verified numerical simulation results combined with the boundary layer theory of solidification front and dendrite breaking–fusing model revealed the dendrite deflection mechanism and growth process. When thermal stress is not considered, and no narrow segment can be found in the dendrite, the velocity magnitude on the solidification front of liquid steel can reach up to 0.041 m/s before the dendrites break. [ABSTRACT FROM AUTHOR]

Highlights: The synergistic "anchor-capture" mechanism of polar groups on Zn stripping/plating process is firstly proposed. The amino group firmly anchors on Zn surface and the carboxyl group strongly captures Zn2+, constructing a robust anode–electrolyte interface and inducing uniform Zn deposition. The ultra-stable cycle lifespan of Zn–Zn symmetric cell (over 2800 h) and high utilization rate of Zn anode (the depth of discharge up to 68% for 200 h) are achieved under the proposal of synergistic "anchor-capture." While the rechargeable aqueous zinc-ion batteries (AZIBs) have been recognized as one of the most viable batteries for scale-up application, the instability on Zn anode–electrolyte interface bottleneck the further development dramatically. Herein, we utilize the amino acid glycine (Gly) as an electrolyte additive to stabilize the Zn anode–electrolyte interface. The unique interfacial chemistry is facilitated by the synergistic "anchor-capture" effect of polar groups in Gly molecule, manifested by simultaneously coupling the amino to anchor on the surface of Zn anode and the carboxyl to capture Zn2+ in the local region. As such, this robust anode–electrolyte interface inhibits the disordered migration of Zn2+, and effectively suppresses both side reactions and dendrite growth. The reversibility of Zn anode achieves a significant improvement with an average Coulombic efficiency of 99.22% at 1 mA cm−2 and 0.5 mAh cm−2 over 500 cycles. Even at a high Zn utilization rate (depth of discharge, DODZn) of 68%, a steady cycle life up to 200 h is obtained for ultrathin Zn foils (20 μm). The superior rate capability and long-term cycle stability of Zn–MnO2 full cells further prove the effectiveness of Gly in stabilizing Zn anode. This work sheds light on additive designing from the specific roles of polar groups for AZIBs. [ABSTRACT FROM AUTHOR]

Interfacial instability, viz., pore formation in the lithium metal anode (LMA) during discharge leading to high impedance, current focusing induced solid–electrolyte (SE) fracture during charging, and formation/behaviour of the solid–electrolyte interphase (SEI), at the anode, is one of the major hurdles in the development of solid‐state batteries (SSBs). Also, understanding cell polarization behaviour at high current density is critical to achieving the goal of fast‐charging battery and electric vehicle. Herein, via in situ electrochemical scanning electron microscopy (SEM) measurements, performed with freshly deposited lithium microelectrodes on transgranularly fractured fresh Li6PS5Cl (LPSCl), the LiǀLPSCl interface kinetics are investigated beyond the linear regime. Even at relatively small overvoltages of a few mV, the LiǀLPSCl interface shows non‐linear kinetics. The interface kinetics possibly involve multiple rate‐limiting processes, i.e., ion transport across the SEI and SE|SEI interfaces, as well as charge transfer across the LiǀSEI interface. The total polarization resistance RP of the microelectrode interface is determined to be ≈ 0.8 Ω cm2. It is further shown that the nanocrystalline lithium microstructure can lead to a stable LiǀSE interface via Coble creep along with uniform stripping. Also, spatially resolved lithium deposition, i.e., at grain surface flaws, grain boundaries, and flaw‐free surfaces, indicates exceptionally high mechanical endurance of flaw‐free surfaces toward cathodic load (>150 mA cm−2). This highlights the prominent role of surface defects in dendrite growth. [ABSTRACT FROM AUTHOR]