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Aqueous zinc‐ion batteries (ZIBs) have triggered a great deal of scientific research and become a promising alternative for large‐scale energy storage applications, owing to the unique merits of high volumetric energy density, abundance of zinc resources, eco‐friendliness, and safety. The pace of progress of ZIB development, however, is hindered by their poor reversibility and sluggish kinetics, derived from the dissolution of active materials in aqueous electrolytes and the strong electrostatic interactions between Zn2+ and the cathode lattice. Herein, a vanadium oxide (V2O5‐x)/polyaniline (PANI‐V) superlattice structure is demonstrated as a model of superlattice structural engineering to overcome these weaknesses. In this superlattice, the PANI layer not only plays the role of a spacer to expand the V2O5‐x interlayer spacing but also serves as a conductive capacity contributor. Moreover, the PANI layer servers as structural stabilizer to restrain the dissolution of V2O5‐x active materials in aqueous electrolytes. In addition, it introduces an interface effect to modulate the charge distribution of the V2O5‐x monolayer, promoting Zn‐ion diffusion into the structure. Correspondingly, weakening the electrostatic interactions and supressing the active materials dissolution synergistically boosts the electrochemical performance for Zn‐ion storage. This work paves the way for the development/improvement of cathodes for aqueous zinc‐ion batteries. [ABSTRACT FROM AUTHOR]

Graphite-nanoplate-coated Bi2S3 composite (Bi2S3@C) has been prepared by a simple, scalable, and energy-efficient precipitation method combined with ball milling. The Bi2S3@C composite was used as the cathode material for sodium-sulfide batteries. It delivered an initial capacity of 550 mAh g−1 and high stable specific energy in the range of 275-300 Wh kg−1 at 0.1 C, with an enhanced capacity retention of 69 % over 100 cycles. The unique structure demonstrates superior cycling stability, with a capacity drop of 0.3 % per cycle over 100 cycles, compared with that of bare Bi2S3. The sodium storage mechanism of Bi2S3 was investigated based on ex situ X-ray diffraction and scanning transmission electron microscopy. [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]

Mn‐based hexacyanoferrate NaxMnFe(CN)6 (NMHFC) has been attracting more attention as a promising cathode material for sodium ion storage owing to its low cost, environmental friendliness, and its high voltage plateau of 3.6 V, which comes from the Mn2+/Mn3+ redox couple. In particular, the Na‐rich NMHFC (x > 1.40) with trigonal phase is considered an attractive candidate due to its large capacity of ≈130 mAh g−1, delivering high energy density. Its unstable cycle life, however, is holding back its practical application due to the dissolution of Mn2+ and the trigonal‐cubic phase transition during the charge–discharge process. Here, a novel hexacyanoferrate (Na1.60Mn0.833Fe0.167[Fe(CN)6], NMFHFC‐1) with Na‐rich cubic structure and dual‐metal active redox couples is developed for the first time. Through multiple structural modulation, the stress distortion is minimized by restraining Mn2+ dissolution and the trigonal‐cubic phase transition, which are common issues in manganese‐based hexacyanoferrate. Moreover, NMFHFC‐1 simultaneously retains an abundance of Na ions in the framework. As a result, Na1.60Mn0.833Fe0.167[Fe(CN)6] electrode delivers high energy density (436 Wh kg−1) and excellent cycle life (80.2% capacity retention over 300 cycles), paving the way for the development of novel commercial cathode materials for sodium ion storage. [ABSTRACT FROM AUTHOR]

Zinc‐ion batteries with chalcogen‐based (S, Se, Te) cathodes have emerged as a promising candidate for utility‐scale energy storage systems and portable electronics, which have attracted rapid attention and offer tremendous opportunities owing to their excellent energy density, on top of the advantages of aqueous Zn batteries including cost‐effectiveness, inherent safety, and eco‐friendliness. Here, a comprehensive overview on the basic mechanism of zinc–chalcogen batteries with their great advantages and intrinsic issues is provided. More detailed recent progress is summarized and the existing challenges with promising strategies are provided as well. First, four specific types of batteries are presented, including: zinc–sulfur, zinc–selenium, zinc–selenium sulfide, and zinc–tellurium batteries. Second, the remaining challenges within chalcogen‐based cathodes in the material preparation, physicochemical properties, and battery performance are summarized and discussed. Meanwhile, a series of constructive strategies are comprehensively put forward for optimizing electrochemical performance. Finally, the future research perspectives of zinc–chalcogen batteries are proposed for the exploration and innovation of next‐generation green zinc storage applications. [ABSTRACT FROM AUTHOR]