Steric Hindrance Effects of Linear/Branched Saccharides at Ceramic-Modified Zinc Anodes Enable Ultrastable Aqueous Al-Zn Hybrid Ion Batteries.

Abstract

Aluminum-based electrolytes and zinc anodes respectively provide aqueous Al-Zn hybrid-ion batteries with high theoretical capacity and reversible plating/stripping behavior. However, parasitic reactions at the zinc anode/aluminum-based electrolyte interface - including dendrite growth, hydrogen evolution, and corrosion passivation - significantly limit cycle life and accelerate capacity degradation. Herein, a comparative investigation of the synergistic effects between glucose (a linear monosaccharide) and sucrose (a branched disaccharide) electrolyte additives with the ZnCr₂O₄ interface of PVDF@ZnCr₂O₄@Zn anodes is conducted, specifically examining spontaneous adsorption, steric hindrance, and conductivity enhancement effects on battery performance. The study reveals that glucose, due to its intrinsic properties and lower steric hindrance, exhibits stronger synergistic effects with the ZnCr₂O₄ interface than sucrose, leading to more effective suppression of parasitic reactions and capacity fade. The glucose/sucrose-modified electrolyte enables the battery to achieve exceptional cycling stability (19,000 and 8,000 cycles) while maintaining high specific discharge capacities (267 and 215 mAh g⁻¹). The synergistic effects between these electrolyte additives and the engineered anode interface present promising strategies and theoretical foundations for developing next-generation high-performance batteries.