Highly stable silica gel-Cu@Zn anode for better performance zinc-ion batteries
摘要
Aqueous zinc-ion batteries (AZIBs) have garnered significant attention as promising energy storage systems due to their inherent safety and cost-effectiveness. However, they still face considerable challenges, including severe corrosion and dendrite formation during cycling, which lead to substantial polarization and eventual short-circuiting. To address these issues, a multifunctional silica gel-Cu@Zn composite coating was fabricated on the surface of zinc foil through an in-situ displacement reaction combined with a coating process. The incorporated copper particles acted as nucleation sites, significantly reducing the nucleation overpotential and providing abundant active sites for zinc-ion deposition. Furthermore, the modified silica gel layer, with its porous structure, effectively suppressed zinc dendrite growth while simultaneously enhancing the surface wettability. As a result of the synergistic interaction between the copper particles and the silica gel layer, the assembled symmetric cells exhibited exceptional stability, maintaining minimal voltage hysteresis over 1300 h of plating/stripping cycles at a current density of 10 mA cm–2. Additionally, the modified anode enabled AZIBs to achieve superior rate capability and cycling stability, sustaining performance over 500 cycles at 0.5 A g–1. These findings demonstrate that the silica gel-modified zinc anode holds significant potential for advancing high-performance AZIBs and may have broader implications for the development of other battery systems.