Aloe Vera-Based Green and Sustainable Electrolyte for Zinc Ion Batteries

Abstract

Aqueous zinc-ion batteries (ZIBs) present significant promises for next-generation energy storage systems. However, challenges such as the zinc (Zn) dendrite formation and parasitic side reactions during Zn plating-stripping hinder their development. Herein, an aloe vera (AV)-based green and sustainable electrolyte is formulated to increase the electrochemical stability of the ZIBs, reducing the free water molecules, and decreasing the hydrogen evolution reaction (HER) and Zn dendrite formation. The obtained results confirm that the AV-based electrolyte enhances the electrochemical stability and boosts the performance of the ZIBs. The formulated AV-based electrolyte in symmetrical Zn//Zn cells demonstrates an outstanding cycle life of 4500 h, significantly longer than the aqueous electrolytes for ZIBs. The quinone moiety of the AV-based electrolytes provides higher specific capacities for VO₂(D) and activated carbon cathodes in full devices. AV-based green electrolytes allow the realization of sustainable and safe energy storage systems for next-generation applications.