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The durability of aqueous zinc-ion batteries (AZIBs) is still impeded due to issues such as dendrite growth, byproduct formation and hydrogen evolution reactions in Zn metal anodes. Herein, we proposed a polydentate ligand, triazole (Ta), as an effective electrolyte additive to prolong the anode stability by its selective adsorption preference and enhanced zinc ion coordination and proton buffering ability. Specifically, Ta induces the formation of an interfacial molecular dam that not only mitigates corrosion via the H2O-deficient electric double-layer (EDL) but also facilitates uniform Zn deposition through its large conjugated planes and zincophilic properties. As a result, a symmetrical cell with the Ta additive exhibits a highly reversible cycle life for 2200 h at 1 mA cm−2 with a capacity of 1 mA h cm−2. Notably, using the Ta/ZnSO4 electrolyte enables stable cycling for 400 h at a high depth-of-discharge (DOD) level of 85%, leading to improved performance in the Zn//α-MnO2 full cell with a lifetime of over 2000 cycles. [ABSTRACT FROM AUTHOR]

For zinc‐metal batteries, the instable chemistry at Zn/electrolyte interphasial region results in severe hydrogen evolution reaction (HER) and dendrite growth, significantly impairing Zn anode reversibility. Moreover, an often‐overlooked aspect is this instability can be further exacerbated by the interaction with dissolved cathode species in full batteries. Here, inspired by sustained‐release drug technology, an indium‐chelated resin protective layer (Chelex‐In), incorporating a sustained‐release mechanism for indium, is developed on Zn surface, stabilizing the anode/electrolyte interphase to ensure reversible Zn plating/stripping performance throughout the entire lifespan of Zn//V2O5 batteries. The sustained‐release indium onto Zn electrode promotes a persistent anticatalytic effect against HER and fosters uniform heterogeneous Zn nucleation. Meanwhile, on the electrolyte side, the residual resin matrix with immobilized iminodiacetates anions can also repel detrimental anions (SO42− and polyoxovanadate ions dissolved from V2O5 cathode) outside the electric double layer. This dual synergetic regulation on both electrode and electrolyte sides culminates a more stable interphasial environment, effectively enhancing Zn anode reversibility in practical high‐areal‐capacity full battery systems. Consequently, the bio‐inspired Chelex‐In protective layer enables an ultralong lifespan of Zn anode over 2800 h, which is also successfully demonstrated in ultrahigh areal capacity Zn//V2O5 full batteries (4.79 mAh cm−2). [ABSTRACT FROM AUTHOR]

Mild aqueous Zn batteries (AZBs) generally suffer a low‐voltage/energy dilemma, which compromises their competitiveness for large‐scale energy storage. Pushing Zn anode potential downshift is an admissible yet underappreciated approach for high‐voltage/energy AZBs. Herein, with a mild hybrid electrolyte containing in situ‐derived diluted strongly‐coordinated Zn2+‐cosolvent pairs, a considerable Zn anode potential downshift is initially achieved for high‐voltage Zn‐based hybrid batteries. The chosen butylpyridine cosolvent not only strongly coordinates Zn2+ ions but also acts as a hydrogen‐bond end‐capping agent to inhibit hydrogen evolution reaction (HER). The electrolyte environment with hetero‐solvation‐diluted strongly‐coordinated Zn2+‐cosolvent pairs remarkably lowers Zn2+ activity, responsible for the Zn electrode potential downshift (−0.330 V vs Zn), confirming to modified Nernst law (ΔE = RTnF$\frac{{RT}}{{nF}}$ln[a(Zn2 +)/a(coordinated solvent)]). With the diluted Zn2+‐containing hybrid electrolyte, the Zn//Zn symmetric cell in the hybrid electrolyte shows a long lifespan over 1270 h at a stripping/plating capacity of 0.4 mA h cm−2. Compared with in common hybrid electrolytes, the as‐assembled Zn‐MnO2 hybrid battery delivers a ca. 0.278 V enhanced voltage plateau (1.57 V) and a long‐term cyclability of over 736 cycles. This work opens a new avenue toward Zn anode potential downshift for high‐voltage AZBs, which can extend to other mild metal batteries. [ABSTRACT FROM AUTHOR]

Aqueous Zn metal batteries hold significant promise for large‐scale energy storage owing to their high safety and low cost. Nevertheless, severe corrosion and uncontrollable dendrite growth hinder the cyclic stability of Zn metal anodes. Herein, a porphyrin‐Zn(II) (ZnTBPP) based multifunctional artificial layer to stabilize Zn anodes by suppression of hydrogen evolution reactions is designed. This hydrophobic interfacial layer repels active water molecules and facilitates the electron transfer from Zn interface to the ZnTBPP layer, thereby increasing the inherent hydrogen evolution potential of Zn anodes. Differential charge density maps reveal that the electron cloud density of the charge transfer layer within the ZnTBPP layer is delocalized due to the electron‐withdrawing effect of Br‐containing functional groups in the ZnTBPP ligands, depleting the interfacial electrons of Zn metal anodes. As a result, H* exhibits a higher Gibbs free energy (∆GH*) of 0.75 eV on Zn with a ZnTBPP coating layer in contrast to bare Zn (0.55 eV), effectively suppressing H2 production. Specifically, the H2 evolution rate of ZnTBPP@Zn (4.06 µmol h−1 cm−2) is ≈2.2 times lower than that of bare Zn. The ZnTBPP@Zn//NaV3O8·1.5H2O full cells exhibit an ultra‐long cycling life of 10 000 cycles at 10 A g−1. [ABSTRACT FROM AUTHOR]

Among six‐electron Te conversion for energetic aqueous Zn batteries, the main capacity contributor, Te0/Te4+ redox usually causes substantial battery capacity/life discount due to its sluggish kinetics/poor reversibility. Herein, for the first time, an offense‐defense‐balanced strategy to simultaneously address the deficiencies is reported. Beyond previous proton‐ or reductant‐regulated solutions, this strategy efficaciously reconciles the pending capacity‐lifespan conflict. As a proof of concept, additive‐level nucleophilic chlorine ions (Cl−) and reductive glucose (Glu) in electrolytes are synergistically employed as "offensiver" and "defender" for Te0/Te4+ conversion, respectively. The Cl−/Glu co‐additive well inherits the nucleophilic motivation effect of Cl− on Te0/Te4+ conversion, and eliminates the formation of Cl−‐induced diffluent metastable phase (γ‐TeO2), enabling a deep and highly reversible Te0/Te4+ redox. Compared with co‐additive‐free electrolytes, the activation energy for Te conversion is lowered (61.4 vs. 52.8 kJ mol−1), and the shuttle of active materials is effectively inhibited. Consequently, Zn‖Te batteries deliver a volumetric capacity of approximately theoretical value (2409 mAh cm−3) at 0.2 A g−1, and a 15∼30‐fold longer lifespan than those in conventional electrolytes (over 5000 cycles with a decay of only 0.15‰ per cycle at 4 A g−1). This work opens a new avenue to develop other chalcogen conversion‐based aqueous Zn batteries. [ABSTRACT FROM AUTHOR]

Layered ammonium vanadate materials exhibit significant mass-specific capacity and ion transport rate due to their small molecular weight and large ionic radius. However, the strong electrostatic interactions of Zn2+ and V-O bonds and the fragile ionic bonding of N-H-O bonds hinder their development. Therefore, this work reports Mg2+ doping NH4V4O10 materials accompanied by flower-like morphology to lower the migration energy barrier and inhibit amine dissolution. Owing to the 3D-flower-like morphology and the combined impact of Mg2+ and structural water, the binding of Zn2+-V-O is significantly enhanced and additional ion channels were constructed. Pre-intercalated Mg2+ enhances the structural integrity and prevents irreversible deammoniation from obtaining excellent cyclic stability. Density functional theory (DFT) calculations show that MNVO provides a smoother Zn2+ diffusion path with a lower migration barrier. Benefited from these advantages, the MNVO cathode exhibits a high specific capacity of 410 mAh g-1 at 0.1 A g-1, satisfactory cyclic stability (90.2 % capacity retention at 10 A g-1 after 5000 cycles), and capable rate ability (118 mAh g-1 at 25 A g-1) within 0.4-1.5 V. Furthermore, the zinc ion storage mechanism in the MNVO cathode is investigated through multiple analyses. [ABSTRACT FROM AUTHOR]