Stable Zinc Anodes Enabled by a Zincophilic Polyanionic Hydrogel Layer

Abstract

The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/adma.202202382. transport. Furthermore, such a hydrogel layer chemically bonded on the Zn surface possesses an anti-catalysis effect, which effectively suppresses both the hydrogen evolution reaction and formation of Zn dendrites. As a result, stable and reversible Zn stripping/plating at various currents and capacities is achieved. A full cell by pairing the Zn-SHn anode with a NaV 3 O 8 •1.5 H 2 O cathode shows a capacity of around 176 mAh g −1 with a retention around 67% over 4000 cycles at 10 A g −1 . This polyanionic hydrogel film protection strategy paves a new way for future Zn-anode design and safe aqueous batteries construction.

A Molecular‐Sieve Electrolyte Membrane enables Separator‐Free Zinc Batteries with Ultralong Cycle Life

“…[5] Among them, surface modification of Zn anode is an effective approach to reconstruct the electrolyte-anode interface. The reported protective layers include inorganic metal compounds such as ZnS, [6] ZnF 2 , [7] CaCO 3 , [8] , CuO, [9] and TiO 2 , [10] and organic polymers like hydrogel, [11] polyamide, [12] and polyethylene oxide. [13] However, most coating layers increase the interfacial resistance and show low ionic conductivity.…”

Triggering Zn2+ Unsaturated Hydration Structure via Hydrated Salt Electrolyte for High Voltage and Cycling Stable Rechargeable Aqueous Zn Battery

“…To overcome these issues and achieve better performance of AZMBs, it is crucial to suppress the presence of free water. [8] Many strategies have been proposed forcing on reducing water activity and concentration, such as electrolyte additives, [9] "water-in-salt" electrolytes, [10] surface engineering, [11] deep eutectic electrolyte, [12] molecular-crowding electrolyte, [13] and organic electrolyte. [14] For example, dimethyl sulfoxide (DMSO) as an electrolyte additive was introduced into aqueous electrolyte to achieve robust H-bond network via the hydrogen bond between the hydrogen atom of water molecule and DMSO, which effectively reduces the activity of water molecules and suppresses the parasitic reactions.…”

Hydrogels Enable Future Smart Batteries

“…Combining the interfacial protection concept with hydrogels provides a distinct idea for stabilizing aqueous batteries. We used a polyanionic hydrogel thin film on a zinc metal anode as the protective layer (Figure c) . The hydrogel layer chemically bonded on the Zn metal surface possesses an anticatalysis effect, which effectively suppresses both the hydrogen evolution reaction and dendrite formation.…”

“…We used a polyanionic hydrogel thin film on a zinc metal anode as the protective layer (Figure 2c). 40 The hydrogel layer chemically bonded on the Zn metal surface possesses an anticatalysis effect, which effectively suppresses both the hydrogen evolution reaction and dendrite formation. As a result, stable and reversible Zn stripping/plating over 1000 h can be realized with a rigorous cutoff condition of 10 mA cm −2 /5 mAh cm −2 .…”