Plasma Enabled Hierarchical Surface Reconstruction of Nanoengineered, Dendrite-Free Zn Metal for Durable Aqueous Zinc...

Aqueous Zinc-ion batteries (AZIBs) are receiving significant attention due to their high volumetric energy density, increased safety and lower cost compared to alternative energy storage systems. The use of Zinc metal as an anode, however, creates stability challenges due to dendrite formation as well as side reactions from surface imperfections. In this work, hierarchical surface modification to Zinc metal anodes via a low energy, scalable Argon plasma is introduced. This approach smooths surfaces and heals defects on a micron scale while simultaneously Zinc nanoisland seed layers are formed. Plasma induced surface reconstruction also leads to a significant reduction in surface impurities. Moreover, Zinc nanoisland seed layers are found to be beneficial for suppressing the dendrite formation through surface homogenization. Unlike unstable and short-lived bare Zn metal anodes, plasma treated anodes exhibits enhanced rate performances and superior stability even after long-term cycling demonstrated by symmetric cell test and full cell tests with both MnO₂ and V₂O₅ cathode tested under different electrolytes. These results demonstrate that plasma enabled surface modification of Zn metal anode is an effective strategy for improving the overall AZIB performance, especially the cycling stability in a facile manner, resolving one of the key challenges to commercializing AZIBs.