Anodic Research Articles

Biomass‐Derived Phosphorus‐Doped Porous Hard Carbon Anode for Stable and High‐Rate Sodium Ion Batteries

Biomass‐derived hard carbon, despite being promising for anode material of sodium‐ion batteries, usually suffer from low initial coulombic efficiency (ICE), poor rate capacity, and limited cycling stability caused by complex surface defects and low intrinsic conductivity. Herein, phosphorus‐doped porous hard carbon (HC@PC‐P) were synthesized by the thermal polymerization of soy lecithin on the surfaces of hard carbon derived from olive kernels. The incorporation of heteroatom phosphorus in the porous hard carbon framework expands the carbon lattice spacing, optimizes the graphitization degree, and increases electrical conductivity, guaranteeing ensuring rapid electron and ion transfer. These coupling effects enable HC@PC‐P anode to achieve a high reversible capacity of 350 mAh g‐1 at 0.1 A g‐1, an impressive initial coulombic efficiency of 89.6%, and remarkable long‐term cycling stability at 1 A g‐1 over 1000 cycles with negligible capacity fade. The mechanisms behind sodium storage and enhanced electrochemical performance were elucidated by ex‐situ Raman spectroscopy and kinetic analysis. Additionally, the assembled HC@PC‐P//Na3V2(PO4)3 full cell demonstrated a high energy density of 257.9 Wh kg‐1. This work provides a rational guide for designing advanced hard carbon anode materials for high‐energy sodium‐ion batteries.

Electrolyte Chemistry Toward Sulfur‐Rich Interphase for Wide‐Temperature Sodium‐Ion Batteries

AbstractAchieving wide‐temperature operation is a crucial objective for the practical deployment of sodium‐ion batteries (SIBs). However, the development of suitable electrolytes is hindered by significant challenges, including compromised ionic dynamics at low temperatures and interphase instability at high temperatures. Herein, this study proposes a novel interphase enhancement mechanism utilizing a sulfur‐rich strategy, grounded in rational solvent selection. This approach enriches the electrolyte with sulfur‐containing species that exhibit high Na+ affinity and efficient ionic migration at both the cathode and anode sides. Consequently, this strategy significantly enhances interfacial charge transfer and interphase integrity, confirmed by theoretical calculations and electrochemical measurements. The designed electrolyte demonstrates robust performance in half‐cells based on Na3V2(PO4)3 (NVP) across a wide temperature range from −25 to 60 °C. Furthermore, the full‐cell, featuring an NVP cathode paired with a hard carbon anode, exhibits exceptional stability. Specifically, the full cell achieves reversible capacities of 56.1 mAh g−1 after 100 cycles at −25 °C and 74.9 mAh g−1 after 100 cycles at 60 °C, with impressive capacity retentions of 87.7% and 88.2%, respectively. Importantly, the study introduces an advanced interphase optimization strategy that enables the operation of SIBs across wide temperatures, providing practical solutions for future developments in the field.

Revealing the Surface and In-Depth Operational Performances of Oxygen-Evolving Anode Coatings: A Guideline for the Synthesis of Inert Durable Anodes in Metal Electrowinning from Acid Solutions

The electrochemical performances of an oxygen-evolving anode produced by the reactivation of waste Ti substrate by a typical IrO2-Ta2O5 coating are correlated to the textural (non)uniformities of the coating and its exhaustion state. Coating degradation is considered operational loss of the activity in a metal electrowinning process. It was found that (pseudo)capacitive performances can vary over the coating surface by 20–30% and depend on the type of dynamics of the input perturbation: constant through cyclic voltammetry (CV) or discontinuous time-dependent through electrochemical impedance spectroscopy (EIS). CV-EIS data correlation enabled profiling of the capacitive properties through the depth of a coating and over its surface. The correlation was confirmed by the findings for the analysis of coating activity for an oxygen evolution reaction, finally resulting in the reliable proposition of a mechanism for the operational loss of the anode. It was found that the less compact and thicker coating parts performed better and operated more efficiently, especially at lower operational current densities.

Ball-on-Disk Wear Maps for Bearing Steel–Hard Anodized EN AW-6082 Aluminum Alloy Tribocouple in Dry Sliding Conditions

In recent years, Golden Hard Anodizing (G.H.A.®) has been developed as a variant of the traditional hard anodizing process with the addition of Ag+ ions in the nanoporous structure. The tribological properties of this innovative surface treatment are still not well understood. In this study, ball-on-disk tests were conducted in dry sliding conditions using 100Cr6 (AISI 52100) bearing steel balls as a counterbody and GHA®-anodized EN AW-6082 aluminum alloy disks. The novelty of this work lies in the mapping of the wear properties of the tribocouple under different test conditions for a better comparison of the results. Three different normal loads (equal to 5, 10, and 15 N) and three different reciprocating frequencies (equal to 2, 3, and 4 Hz) were selected to investigate a spectrum of operating conditions for polished and unpolished G.H.A.®-anodized EN AW-6082 aluminum alloy. Quantitative wear maps were built based on the resulting wear rate values to define the critical operating limits of the considered tribocouple. The results suggest that the coefficient of friction (COF) was independent of test conditions, while different wear maps were found for polished and non-polished surfaces. Polishing before anodizing permitted the acquisition of lower wear for the anodized disks and the steel balls.

Improving Oxygen-Redox-Active Layered Oxide Cathodes for Sodium-Ion Batteries Through Crystal Facet Modulation and Fluorinated Interfacial Engineering.

Layered oxides with active oxygen redox are attractive cathode materials for sodium-ion batteries (SIBs) due to high capacity but suffer from rapid capacity/voltage deterioration and sluggish reaction kinetics stemming from lattice oxygen release, interfacial side reactions, and structural reconstruction. Herein, a synergistic strategy of crystal-facet modulation and fluorinated interfacial engineering is proposed to achieve high capacity, superior rate capability, and long cycle stability in Na0.67Li0.24Mn0.76O2. The synthesized single-crystal Na0.67Li0.24Mn0.76O2 (NLMO{010}) featuring increased {010} active facet exposure exhibits faster anionic redox kinetics and delivers a high capacity (272.4 mAh g-1 at 10mA g-1) with superior energy density (713.9Wh kg-1) and rate performance (116.4 mAh g-1 at 1 A g-1). Moreover, by incorporating N-Fluorobenzenesulfonimide (NFBS) as electrolyte additive, the NLMO{010} cathode retains 84.6% capacity after 400 cycles at 500mA g-1 with alleviated voltage fade (0.27mV per cycle). Combined in situ analysis and theoretical calculations unveil dual functionality of NFBS, which results in thin yet durable fluorinated interfaces on the NLMO{010} cathode and hard carbon anode and scavenges highly reactive oxygen species. The results indicate the importance of fast-ion-transfer facet engineering and fluorinated electrolyte formulation to enhance oxygen redox-active cathode materials for high-energy-density SIBs.

A Universal Interfacial Reconstruction Strategy Based on Converting Residual Alkali for Sodium Layered Oxide Cathodes: Marvelous Air Stability, Reversible Anion Redox, and Practical Full Cell.

Mn-based layered oxide cathodes have attracted widespread attention due to high capacity and low cost, however, poor air stability, irreversible phase transitions, and slow kinetics inhibit their practical application. Here, we propose a universal interfacial reconstruction strategy based on converting residual alkali to tunnel phase Na0.44MnO2 for addressing the above mentioned issue simultaneously, using O3 NaNi0.4Fe0.2Mn0.4O2@2 mol % Na0.44MnO2 (NaNFM@NMO) as the prototype material. The optimized material exhibits an initial capacity and energy density comparable with lithium-ion batteries. The reversible anionic redox behavior and charge compensation mechanism of NaNFM@NMO were analyzed and verified by soft X-ray absorption spectrum and in situ X-ray absorption spectrum. Due to the intrinsic stability of the tunnel structure, excellent air stability and highly reversible structure evolution of the NaNFM@NMO cathode material are achieved, which are confirmed by contact angle test, rigorous aging test, and in situ X-ray diffraction. More importantly, the NaNFM@NMO cathode demonstrates a great match with the nonpresodiated hard carbon anode and shows excellent electrochemical performance of the full cell. Additionally, such a strategy could be also applied to modify P2-type cathodes, showing superior universality and good prospects in industrialized production. Overall, the proposed strategy could improve air stability while remaining interfacial and bulk stable simultaneously and will open up a whole new field for the optimization of other electrode materials.

Effect of concentration of dextrose-derived hard carbon anode on the electrochemical performance for sodium-ion batteries

Effect of concentration of dextrose-derived hard carbon anode on the electrochemical performance for sodium-ion batteries

Synergistic Long-Term Protection of Inorganic and Polymer Hybrid Coatings for Free-Dendrite Zinc Anodes.

Constructing an artificial solid electrolyte interface protective layer on the surface of the zinc anode is an effective strategy for addressing dendrite growth, passivation, and the hydrogen evolution reaction in aqueous zinc-ion batteries. This study introduces a robust interlayer composed of a polyvinyl butyral matrix decorated with SiO2 particles (PS). Adsorption of water by Si-OH on the surface of SiO2 leads to excellent hydrophilicity and accelerates the desolvation of ions. A highly stable and hydrophilic PS coating enhances ion migration and possesses ultralong protection ability, ensuring uniform ion deposition and a lower nucleation barrier. Anodes protected by the PS coating achieve long-term cycling stability of >4000 h at 2 mA cm-2 in symmetric cells. The assembled PS-Zn//NH4V4O10 full cells exhibit superior electrochemical performance, demonstrating their potential for practical applications in rechargeable zinc batteries.

Lattice sulfuration enhanced sodium storage performance of Na0.9Li0.1Zn0.05Ni0.25Mn0.6O2 cathode

Introducing lattice oxygen redox for charge compensation in layered metal oxides is an effective way to develop advanced cathodes for high energy density sodium-ion batteries (SIBs). However, the asymmetry of lattice oxygen oxidation and reduction incurs oxygen release and crystal structure rearrangement, leading to poor reversibility of the charge and discharge process. Herein, a Na2S-assisted sulfuration strategy is firstly proposed to incorporate active sulfur into the crystal lattice of Na0.9Li0.1Zn0.05Ni0.25Mn0.6O2 cathode. The sulfur anions within the interior lattice participate in the redox process and enhance the integral coordination stability by mitigating undesired excessive oxygen redox, while the exterior sulfur forms a polyanionic layer to protect the particle surface against electrolyte corrosion. The incorporation of an extra redox center efficiently facilitates the increase of the discharge capacity from 159.9 to 179.2 mAh g−1 within the voltage range of 1.5–4.5 V. Moreover, the larger ionic radius of sulfur enlarges the interplanar spacing, thus facilitating Na+ ions transfer, especially at high current density. As a result, the modified cathode exhibits significantly enhanced electrochemical performance, with a capacity retention of 87 % after 100 cycles at 0.2 C and an excellent rate capability of 98.0 mAh g−1 at 10 C. Moreover, the assembled Na ion full cell based on a commercial hard carbon anode achieves an impressive capacity of 160.4 mAh g−1 at 0.1 C and could cycled steadily for over 100 cycles. The modification of layer oxides via sulfuration strategy provides a promising pathway for the structural design of novel cathodes with superior cycle performance for high-energy-density SIBs applications.

Structural Regulation of P2‐Type Layered Oxide with Anion/Cation Codoping Strategy for Sodium‐Ion Batteries

AbstractP2‐type layered transition metal oxides are potential cathodes for sodium‐ion batteries (SIBs), but they commonly suffer from severe capacity degradation owing to multiple phase transitions and Na+/vacancy ordering during the extraction/insertion process. An anionic/cationic co‐doping strategy at high sodium contents is proposed to effectively achieve high‐rate and long‐term stability of P2‐Na0.67Ni0.33Mn0.67O2. The resulting Na0.75Mg0.1Ni0.23Mn0.67O1.95F0.05 (NMNMOF) cathode delivers a reversible capacity of 116 mAh g−1 at 75 mA g−1 and maintains an initial capacity of 73% at 1500 mA g−1 after 1000 cycles. The Mg/F anionic/cationic co‐doping strategy impacts the local environment of the surrounding transition metal and oxygen, regulates the electron distribution, and modifies the initial diffusion state of Na sites, enhancing the diffusion ability of Na+. Moreover, the phase transition of P2‐O2 is well suppressed and the decrease in Mn3+ content greatly alleviates the Jahn–Teller effect to enhance structural stability. The full‐cell devices with NMNMOF cathode and hard carbon anode demonstrate a high capacity of 80 mAh g−1 at 10 C and an excellent cycle life of over 500 cycles for applications. The anionic/cationic co‐doping strategy will inspire the rational design of P2‐type layered oxides and provide a new perspective for advanced SIBs.

High-viscoelasticity alginate-based coatings for reversible zinc metal anodes

High-safety aqueous zinc (Zn) ion batteries are troubled by dendrite growth and hydrogen evolution reaction on Zn anode, which can be well solved via the construction of surface protective layer. The recent researches mainly focus on the bulk property of the protective layer, but its separation from Zn anode is ignored. In this work, high-viscoelasticity alginate-based (HVAA) layer was in-situ constructed on Zn anodes by the cross-linking of sodium alginate with formaldehyde and the plastifying of glycerin. HVAA layer can combine with H2O and coordinate with Zn2+ ions in aqueous electrolyte to achieve viscoelasticity on Zn anode, which can accommodate volume change of Zn anode during plating/stripping processes to continuously protect Zn anodes under the real battery system. Physical block effect of HVAA layer impedes hydrogen evolution corrosion reaction by avoiding the immediate contact of Zn anodes with aqueous electrolyte. Ionic conductive ability of HVAA layer by coordinating oxygen-containing groups with Zn2+ can uniform ion flux to induce the homogeneous deposition of Zn2+ on Zn anode. Zn anode with HVAA endows ZnZn symmetric battery with stably cycle of 4000 h and Zn-iodide full batteries with better electrochemical performance of 8000 cycles comparing with bare Zn anode. This work opens a novel route to continuously protect Zn anode through the high-viscoelasticity films to closely fit with Zn surface and implement the high-value application of renewable sources.

Construction of an Anode Material for Sodium-Ion Batteries with an Ultrastable Structure.

The reserves of sodium resources are much larger than those of lithium resources, and they are widely distributed and easy to produce and can be widely used in photovoltaic energy storage and other industries on the premise of this advantage. However, how to produce hard carbon anodes at a low cost for the preparation of energy storage materials requires continuous exploration and experimentation to find the optimal solution. Here, we used waste sour date shell biomass as a precursor for a hard carbon anode obtained by simple acid treatment and two pyrolyses. It is shown that acid washing after prepyrolysis has a significant effect on the electrochemical performance of the sour date shell-derived hard carbon (ZJ), constructing a stable structure that makes it easier for sodium ions to be embedded and dislodged, and the carbon particles are homogeneous and free of bonding and electrode cracking. The ZJ-1500-HCl pyrolyzed at 1500 °C has a high reversible capacity of 329.1 mAh g-1, 94.1% initial Coulombic efficiency (ICE), 90.54% capacity retention efficiency cycling 300 cycles at a current density of 300 mA g-1, and a resistivity below 10 Ω. It has good cycle stability and a good multiplier performance. It is expected to be used in practical production and photovoltaic energy storage in the future.

Tribological Properties of 7A04 Aluminum Alloy Enhanced by Ceramic Coating

The 7A04 Al alloy is a commonly used lightweight metal material; however, its low wear resistance limits its application. In this study, the wear resistance of this alloy was improved by preparing micro-arc oxidation (MAO) coatings, MAO/MoS2 composite coatings, and hard-anodized (HA) coatings on its surface. The friction and wear behaviors of these three coatings with diamond-like coated (DLC) rings under oil lubrication conditions were investigated using a ring–block friction tester. The wear rates of the coatings on the block surfaces were determined using laser confocal microscopy, and the wear trajectories of the coatings were examined using scanning electron microscopy. The results indicated that, among the three coatings, the MAO/MoS2 coating had the lowest coefficient of friction of 0.059, whereas the HA coating had the lowest wear rate of 1.47 × 10−6 mm/Nm. The MAO/MoS2 coatings exhibited excellent antifriction properties compared to the other coatings, whereas the HA coatings exhibited excellent anti-wear properties. The porous structure of the MAO coatings stored lubricant and replenished the lubrication film under oil lubrication. Meanwhile, the introduced MoS2 enhanced the densification of the coating and functioned as a solid lubricant. The HA coating exhibited good wear resistance owing to the dense structure of the amorphous-phase aluminum oxide. The mechanisms of abrasive and adhesive wear of the coatings under oil lubrication conditions and the optimization of the tribological properties by the solid–liquid synergistic lubrication effect were investigated. This study provides an effective method for the surface modification of Al alloys with potential applications in the aerospace and automotive industries.

Synthesis of a Hard Anodic Oxide Coating with a Structure Allowing for Its Modification by Nanoparticles

A hard anodic oxide coating’s characteristic porous structure allows for its modification by the incorporation of nanoparticles. However, achieving an appropriate microstructure requires an optimal pore arrangement and shape, which is influenced by the electrolyte composition, current densities, temperature, and processing time. To achieve pores with a diameter of about 50 nm and the most regular structure, a range of these parameters were tested. Using a two-stage manufacturing process had a beneficial effect on increasing the microporosity of the coating. The addition of phthalic acid at 0 °C did not increase the pore diameter, but allowed for the process to be carried out at higher temperatures. However, the coating produced at 20 °C had a larger pore diameter, but numerous defects. The coating obtained from the three-component solution had the most regular structure, but the smallest pore diameter.

Effect of Presodiation Additive on Structural and Interfacial Stability of Hard Carbon | P2‐Na0.66Mn0.75Ni0.2Mg0.05O2 Full Cell

AbstractThe compatibility between a corncob‐derived hard carbon anode and a layered oxide cathode (Na0.66Mn0.75Ni0.2Mg0.05O2), as well as the effect of presodiation via cathode additive (Na2C4O4), are investigated in a sodium‐ion full cell. Extensive physicochemical and electrochemical characterizations are performed to deeply investigate the structural and interfacial evolution of the materials in the presodiated cell, either within the single cycle or upon long‐term cycling. The use of sacrificial cathode additives is generally regarded as a method to improve full cell performance, especially when using sodium‐deficient materials. However, undesired effects upon decomposition of the sacrificial salt may arise due to the complexity of the system. In this study, it is evidenced that the presodiation changes the properties of the electrodes causing a worsening of the electrochemical performance of the cell during long‐term cycling. The surface morphology of the cathode is negatively affected by the formation of holes/cracks, while redox processes associated with structural transformations are suppressed in the voltage window of interest, with partial structural deformations occurring during activation cycles. The SEI and CEI are also affected by the formation of insulating organic species, which lead to an increased thickness and interphase resistance hampering the charge transfer kinetics of the cell.

A Customized Strategy Realizes Stable Cycle of Large-Capacity and High-Voltage Layered Cathode for Sodium-Ion Batteries.

High-voltage P2-Na0.67Ni0.33Mn0.67O2 layered oxide cathode exhibits significant potential for sodium-ion batteries, owing to the elevated operating voltage and theoretical energy density beyond lithium iron phosphate, but the large-volume phase transition is the devil. Currently, this type cathode still suffers from stability-capacity trade-off dilemma. Herein, a concept of customized strategy via multiple rock-forming elements trace doping is presented to address the mentioned issue. The customized Mg-Al-Ti trace doped cathode maintains a notable capacity of 140.3 mAh g-1 with an energy density approaching 500 Wh kg-1, and shows good cycle stability, retaining 89.0 % of its capacity after 50 cycles at 0.1 C. Additionally, the full cell, paired with a hard carbon anode, achieves an advanced energy density of 303.3 Wh kg-1. The multiple characterizations reveal the failure mechanism of contrast sample involving severe intragranular cracks coupled with layer to rock salt transformation, which reduces active substance and increases charge transfer resistance. The doped sample with increased sliding energy barrier well suppresses this phenomenon. Impressively, the customized strategy can be extended to Mg-Fe-Ti system. This research provides a novel concept for the design of high energy sodium-ion cathode.

A Customized Strategy Realizes Stable Cycle of Large‐Capacity and High‐Voltage Layered Cathode for Sodium‐Ion Batteries

AbstractHigh‐voltage P2‐Na0.67Ni0.33Mn0.67O2 layered oxide cathode exhibits significant potential for sodium‐ion batteries, owing to the elevated operating voltage and theoretical energy density beyond lithium iron phosphate, but the large‐volume phase transition is the devil. Currently, this type cathode still suffers from stability–capacity trade‐off dilemma. Herein, a concept of customized strategy via multiple rock‐forming elements trace doping is presented to address the mentioned issue. The customized Mg‐Al‐Ti trace doped cathode maintains a notable capacity of 140.3 mAh g−1 with an energy density approaching 500 Wh kg−1, and shows good cycle stability, retaining 89.0 % of its capacity after 50 cycles at 0.1 C. Additionally, the full cell, paired with a hard carbon anode, achieves an advanced energy density of 303.3 Wh kg−1. The multiple characterizations reveal the failure mechanism of contrast sample involving severe intragranular cracks coupled with layer to rock salt transformation, which reduces active substance and increases charge transfer resistance. The doped sample with increased sliding energy barrier well suppresses this phenomenon. Impressively, the customized strategy can be extended to Mg‐Fe‐Ti system. This research provides a novel concept for the design of high energy sodium‐ion cathode.

Unravelling the electrochemical characteristics and sodium storage mechanism of pistachio shell derived hard carbon as high plateau capacity anodes by operando Raman spectroscopy and full cell demonstration

Hard carbon has emerged as a highly promising material for negative electrode in sodium-ion batteries (SIBs). This study focuses on the synthesis of an anode material through the pyrolysis of Pistachio shells, a commonly available nut waste, at different temperatures ranging from 900° to 1400°C. The material pyrolyzed at 1400 °C exhibits a remarkable reversible discharge capacity of 302 mAhg−1 and plateau capacity of 223 mAhg−1 at a current rate of 10 mAg−1, displaying stable cyclic performance and an impressive 80% capacity retention after 500 cycles at 200 mAg−1. The morphological, structural, and surface chemical characteristics of the cycled hard carbon anode materials were examined through ex-situ FE-SEM, XRD, and XPS analyses. Furthermore, the sodiation and desodiation mechanisms of the synthesized hard carbon were investigated using operando Raman Spectroscopy. The diffusion kinetics parameters were determined by Electrochemical Impedance Spectroscopy (EIS) and CV analyses. This study underscores the potential of Pistachio shells as a promising precursor for the synthesis of carbonaceous anode for SIBs, employing a straightforward one-step pyrolysis process. The excellent electrochemical performance, along with the ease of material sourcing and synthesis, places this nutty waste as a promising, sustainable and clean energy resource option for advancing sodium-ion battery technology.

Innovative synthesis and sodium storage enhancement of closed-pore hard carbon for sodium-ion batteries

Hard carbon with abundant closed-pore structures holds significant promise as an anode material for sodium-ion batteries. In this work, a one-step process was pioneered to produce porous carbon with abundant open-pore structures from walnut shells. Subsequently, small aromatic compounds derived from the pyrolysis of polystyrene were deposited into the pores of the porous carbon, forming hard carbon material with abundant closed-pore structures. The resulting hard carbon anode (WS-PS-1200) demonstrated a high capacity of 385 mAh g−1 at 50 mA g−1, with a corresponding plateau capacity of 225 mAh g−1. It also exhibited an impressive initial Coulombic efficiency (ICE) of 88 % and excellent rate performance, compared to an ICE of only 57.5 % in the anode obtained by direct carbonization. By utilizing 3D time-of-flight secondary-ion mass spectrometry (3D TOF-SIMS) and depth-profiling X-ray photoelectron spectroscopies (XPS) characterization methods to analyze the solid electrolyte interface (SEI), the results indicate that reducing the open-pore structure can minimize the decomposition of the electrolyte, leading to an SEI composition that tends towards inorganic phases. To verify the practical applicability of WS-PS-1200, it was assembled into a full cell with Na3V2(PO4)3, achieving a capacity of 305 mAh g−1 (0.03 A g−1) and excellent rate performance. Moreover, the assembled all-carbon sodium-ion hybrid capacitor exhibits an energy density of 101 Wh kg−1. This study not only introduces a new strategy for preparing hard carbon with closed pores but also successfully converts waste polystyrene and walnut shells into high-value materials, offering an innovative method for synthesizing hybrid capacitor electrode materials.

Mechanism-Guided Rational Design of Anode Coatings for Aqueous Zinc Ion Batteries.

Aqueous zinc ion batteries (ZIBs) hold promises as a safer, more cost-effective, and environmental-friendly alternative to lithium-ion batteries, especially for stationary energy storage. Recent advancements in protective anode coatings, which fine-tune zinc ion solvation structure, have yielded significant improvements in the aqueous ZIB performance, addressing dendrite formation and side reactions, thereby prolonging cycle lifetime. Understanding the underlying mechanisms of these coatings as ions sieves is crucial for further optimization and achieving long-term stability, which is a key requirement for practical applications. This concept explores recent developments in ZIB anode coatings from the view of molecular mechanisms and points out future research directions.