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The main obstacle for developing aqueous zinc-ion batteries (ZIBs) with long-term stability lies in the suppression of side reactions and zinc dendrites, which are derived from decomposition of active water molecules belonging to Zn2+ solvation layer in the electrolyte. Herein, an inorganic colloidal electrolyte composed of lithium magnesium silicate and zinc sulfate (LMS+ZSO) is utilized to improve the reversibility of Zn plating/stripping behavior for high-performance ZIBs. As revealed by the experimental and theoretical results, LMS's superior adsorption capacity for water molecules modulates the Zn2+ solvation structure via converting the free water molecules into adsorbed water of LMS and weakening the electrostatic coupling of anions and cations, thus restraining the corrosion, hydrogen evolution reaction and by-products. Concomitantly, the LMS lowers the energy barrier of de-solvation process to promote the Zn2+ ions transfer kinetics and induce the homogeneous deposition, thus inhibiting the dendrites formation. Consequently, the cycling stability of symmetric battery and zinc-based full battery are significantly boosted with LMS+ZSO electrolyte. This reasonable and effective strategy offers a promising prospect for developing long life ZIBs. [Display omitted] • Lithium magnesium silicate (LMS) can regulate the solvation structure via adsorbing the free water molecules. • LMS in electrolyte can lower the energy barrier of de-solvation process and increase the Zn2+ transfer number. • The inorganic colloidal electrolyte (LMS+ZSO) can suppress the dendrites growth and by-products. • The cycling stability of symmetric battery and zinc-based full battery are boosted via LMS+ZSO electrolyte. [ABSTRACT FROM AUTHOR]

Aqueous zinc-ion batteries (ZIBs) are recognized as a highly competitive electrochemical energy storage systems due to the high safety and low cost, however, rational design of advanced cathodes with stable internal structures and fast Zn2+ diffusion channel remains challenging. Herein, we reported an advanced cathode of oxygen defect enriched (NH 4) 2 V 10 O 25 ·8H 2 O (NVO D) nanosheets with expanded tunnel structure, exceptional conductivity and superior structural stability for aqueous ZIBs, showing fast Zn2+ diffusion and excellent performance. The resulted ZIBs afford a remarkably high capacity (408 mAh g−1 at 0.1 A g−1), ultrahigh stability (94.1% retention over 4000 cycles), and exceptional energy density (287 Wh kg−1), outperforming many cathodes of ZIBs. Furthermore, it is revealed that from theoretical and experimental studies the oxygen defects intrinsically contribute to the narrow bandgap and high electrical conductivity of NVO D to greatly boost the performance. The reversible storage of Zn2+ in NVO D is further illustrated via different in-situ characterization techniques. Moreover, the flexible soft-packaged batteries also demonstrate superior capacity retention of 91% after 200 cycles. Therefore, the exploration in NVO D materials with rich oxygen defects will supply an attractive approach for designing high-performance and flexible ZIBs. The oxygen defect enriched (NH 4) 2 V 10 O 25 ·8H 2 O (NVO D) nanosheets with expanded tunnel structure, exceptional conductivity and superior structural stability display fast Zn2+ diffusion and excellent performance as cathode of aqueous ZIBs. [Display omitted] • Oxygen defect enriched (NH 4) 2 V 10 O 25 ·8H 2 O (NVO D) nanosheets are synthesized by solution synthesis method. • NVO D nanosheets show the expanded tunnel structure, exceptional conductivity, and superior structural stability. • NVO D nanosheets display high capacity of 418 mAh g−1, and exceptional stability with a retention of 94.1% after 4000 cycles at 5 A g−1. • The soft-packaged ZIBs display long-term cyclability of 91% after 200 cycles, with remarkable flexibility, and modular integration. [ABSTRACT FROM AUTHOR]