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Wadsley–Roth phase niobium‐based oxides show potential as anode candidates for fast‐charging lithium‐ion batteries. Traditional synthesis methods, however, usually involve a time‐consuming calcination process, resulting in poor production efficiency. Herein, a novel carbothermal shock (CTS) method that enables the ultra‐fast synthesis of various Wadsley–Roth phase Nb‐based oxides within seconds is introduced. The extremely rapid heating rates enabled by CTS alter the reaction mechanism from a sluggish solid‐state process to a swift liquid‐phase assisted one and drive the chemical reactions away from equilibrium, thereby generating abundant oxygen vacancies and dislocations. Theoretical calculations reveal that oxygen vacancies significantly lower the energy barrier for Li+ diffusion and enhance the intrinsic electronic conductivity. Moreover, dislocations help convert the surface tensile stress arising from Li+ intercalation into compressive stress, effectively improving the structural integrity during cycling. Notably, this approach can also be applied to synthesize LiFePO4 cathode materials under ambient conditions, eliminating the requirement for inert atmospheres. Consequently, the CTS‐synthesized Nb14W3O44||LiFePO4 battery demonstrates reversible structural evolution validated by in situ XRD and exceptional cycling ability (e.g., 0.0065% capacity decay per cycle at 4 A g−1 over 3000 cycles). Importantly, the Nb14W3O44||LiFePO4 configuration also shows enhanced thermal stability in the Ah‐level pouch cell nail penetration test, confirming its feasibility. [ABSTRACT FROM AUTHOR]

Aqueous zinc–iodine (Zn–I2) batteries, with their outstanding merits in safety, cost, and environmental friendliness, have received extensive attention. However, the unstable electrochemistry at the electrode–electrolyte interface originating from free water results in zinc dendrite growth, hydrogen evolution reaction (HER), and polyiodide ions shuttle, hindering their practical applications. Herein, solid‐state Zn–I2 batteries based on an inorganic ZnPS3 (ZPS) electrolyte are developed to overcome inherent interfacial issues associated with aqueous electrolytes. The inorganic ZnPS3 electrolyte, with a low Zn2+ diffusion energy barrier of ≈0.3 eV, demonstrates an exceptional ion conductivity of 2.0 × 10−3 S cm−1 (30 °C), which also satisfies high chemical/electrochemical stability and mechanical strength. The solid Zn2+ conduction mechanism, facilitated by bounded water only on grains, effectively suppresses HER and polyiodide ions shuttling. During cycling, a ZnS functional layer is spontaneously formed on the anode/electrolyte interphase, promoting dendrite‐free Zn deposition behavior with a more stable (002) crystal orientation. Consequently, the solid‐state configuration of Zn–I2 battery enables an impressive reversible capacity of 154.2 mAh g−1 after 400 cycles at 0.1 A g−1. Importantly, the compatibility of the solid‐state ZnPS3 electrolyte is also confirmed in the Zn||CuS cell, indicating its potential as a versatile platform for developing inorganic solid‐state zinc‐ion batteries (ZIBs). [ABSTRACT FROM AUTHOR]

Zn−I2 batteries stand out in the family of aqueous Zn‐metal batteries (AZMBs) due to their low‐cost and immanent safety. However, Zn dendrite growth, polyiodide shuttle effect and sluggish I2 redox kinetics result in dramatically capacity decay of Zn−I2 batteries. Herein, a Janus separator composed of functional layers on anode/cathode sides is designed to resolve these issues simultaneously. The cathode layer of Fe nanoparticles‐decorated single‐wall carbon nanotubes can effectively anchor polyiodide and catalyze the redox kinetics of iodine species, while the anode layer of cation exchange resin rich in −SO3− groups is beneficial to attract Zn2+ ions and repel detrimental SO42−/polyiodide, improving the stability of cathode/anode interfaces synergistically. Consequently, the Janus separator endows outstanding cycling stability of symmetrical cells and high‐areal‐capacity Zn−I2 batteries with a lifespan over 2500 h and a high‐areal capacity of 3.6 mAh cm−2. [ABSTRACT FROM AUTHOR]

Zn-I 2 batteries stand out in the family of aqueous Zn-metal batteries (AZMBs) due to their low-cost and immanent safety. However, Zn dendrite growth, polyiodide shuttle effect and sluggish I 2 redox kinetics result in dramatically capacity decay of Zn-I 2 batteries. Herein, a Janus separator composed of functional layers on anode/cathode sides is designed to resolve these issues simultaneously. The cathode layer of Fe nanoparticles-decorated single-wall carbon nanotubes can effectively anchor polyiodide and catalyze the redox kinetics of iodine species, while the anode layer of cation exchange resin rich in -SO 3 - groups is beneficial to attract Zn 2+ ions and repel detrimental SO 4 2- /polyiodide, improving the stability of cathode/anode interfaces synergistically. Consequently, the Janus separator endows outstanding cycling stability of symmetrical cells and high-areal-capacity Zn-I 2 batteries with a lifespan over 2500 h and a high-areal capacity of 3.6 mAh cm -2 ., (© 2023 Wiley-VCH GmbH.)