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Although aqueous Zn batteries have become a more sustainable alternative to lithium‐ion batteries owing to their intrinsic security, their practical applications are limited by dendrite formation and hydrogen reactions. The first application of a rare earth metal type addition to Zn batteries, cerium chloride (CeCl3), as an effective, low‐cost, and green electrolyte additive that facilitates the formation of a dynamic electrostatic shielding layer around the Zn protuberance to induce uniform Zn deposition is presented. After introducing CeCl3 additives, the electrochemical characterizations, in situ optical microscopy observation, in situ differential electrochemical mass spectrometry, along with density functional theory calculations, and finite element method simulations reveal resisted Zn dendritic growth and enhanced electrolyte stability. As a result, the Zn–Zn cells using the CeCl3 additive exhibit a long cycling stability of 2600 h at 2 mA cm−2, an impressive cumulative areal capacity of 3.6 Ah cm−2 at 40 mA cm−2, and a high Coulombic efficiency of ≈99.7%. The fact that the Zn–LiFePO4 cells with proposed electrolyte retain capacity significantly better than the additive‐free case is even more exciting.

V vs the standard hydrogen electrode), ultrahigh theory capacity (820 mAh g −1 ), low cost, fast kinetics, and superior reliability, aqueous zinc-ion batteries (ZIBs) have attracted extensive attention among various rechargeable batteries. [5][6][7][8] However, the energy density and output power density of state-of-the-art ZIBs are mainly limited by the unsatisfactory cathode materials, especially under the commercial mass loading (> 10 mg cm −2 ). [9,10] Considerable research efforts have been put into the design of high performance cathode hosts, including Mn-based, V-based transition metal oxides/sulfides, Prussian blue analogues, and organic compounds. [11][12][13] Compared to intercalation-type inorganic counterparts with unstable structures and sluggish ionic diffusion, organic cathodes are promising candidates for advanced aqueous ZIBs due to their lightweight, sustainable, flexible, and tunable structures. [12,14,15] During energy storage/release process of Zn-organic batteries, the cations (Zn 2+ or H + ) are only act to coordinate the charge of active functional group based redox reactions. [16][17][18] Hence, the merely chemical bond rearrangement in organic hosts can contribute to the improved rate capability and cycling stability of ZIBs. [19][20][21] In the past few years, a lot of organic and organic-inorganic hosts have been successfully reported as cathodes for high performance ZIBs. However, the reported polyaniline (PANI) intercalated MnO 2 , [22] PANI intercalated V 2 O 5 , [23] and polypyrrole (PPy) encapsulated Mn 2 O 3 cathodes with the enhanced rate performances were based on the mass loading less than 3 mg cm −2 , which is not conducive to the practical application of aqueous zinc ion batteries. [24] To date, the reversible electrochemical reactions between cations and redox groups of CO, CN, and CN have been studied in Zn-organic batteries. [25][26][27][28] For instance, Chen's group first reported cially calix (C4Q) cathode for building high capacity and long lifespan Zn-organic batteries, yet their large scale applications are limited by the complex synthesis process. [29] Stoddart's group studied phenanthrenequinone-based macrocycle (PQ-Δ) organic cathode, which demonstrates the insertion of hydrated zinc ions and robust triangular structure are benefit to achieve Zn-organic batteries with superior stability. [30] Yet, their low redox potential and unsatisfactory capacity have no obvious advantage than that of inorganic cathodes. In addition to carbonyl active centers of CO, Niu's group also reported diquinoxalino [2,3-a:2′,3′-c] phenazine (HATN) cathode with Organic cathode materials with redox-active sites and flexible structure are promising for developing aqueous zinc ion batteries with high capacity and large output power. However, the energy storage of most organic hosts relies on the coordination/incoordination reaction between Zn 2+ /H + and a single functional group, which result in inferior capacity, low discharge platform, and structural instability. Here, the lead is ...

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Hydrogel is a polymer material with a porous network structure, which allows the hydrogel to swell rapidly underwater without dissolving. This unique property of hydrogels lays the foundation for its...