Inorganic-organic hybrid heterogeneous membrane for zinc protective layers in high-performance aqueous zinc ion batteries

Abstract

Aqueous zinc-ion Batteries (AZIBs) suffer from stability and performance limitations due to challenges related to the zinc (Zn) metal anode, including hydrogen evolution reaction (HER), metal corrosion, and Zn dendrite formation. To mitigate these issues, researchers are developing innovative coatings and protective layers for Zn anodes, focusing on enhancing ion conductivity, electrochemical inertness, mechanical strength, and processability. Hybrid organic-inorganic heterostructure coating materials with silver nanowires (Ag NWs) encapsulated with Polypyrrole (Ag/PPy) have shown promise in addressing these challenges. The Zn anode coated with Ag/PPy layers and paired with an α-MnO2 cathode, achieved an impressive initial capacity of 302 mAh/g at a current density of 0.5 A/g. Remarkably, it retained a substantial capacity of 283 mAh/g after 300 cycles at a current density of 0.5 A/g, demonstrating a 94 % capacity retention rate. Moreover, the symmetry cell using this anode maintains stable Zn deposition/stripping overpotentials even at a high current density (a rate of 10C) for over 175 h. These findings highlight the potential of Ag/PPy coatings as a viable approach for enhancing the surface chemistry and physical properties of the Zn metal anode, paving the way for a wider use of AZIBs.