Sandpaper grinding stable interface for reversible and durable zinc metal anode

摘要

Zinc-ion batteries (ZIBs) are promising energy storage system owing to the low cost and high safety fea-tures. As the most-used anode material, zinc metal always encounters poor coulombic efficiency (CE) and cycling stability, because of the serious zinc dendrite and harmful side reactions on Zn surface. Here, a solid -phase non-adhesive homogeneous Nano-Si layer has been embedded on the Zn surface (Zn-Si) via an ultra -facile grinding method. The Nano-Si layer can regulate an even electric field distribution to achieve a homogeneous zinc deposition, and it also can greatly lower the charge transfer resistance and nucleation energy barrier of Zn2+ to facilitate the zinc deposition, thus achieving a dendrites-free and long-life Zn anode. Encouragingly, the zinc symmetrical battery with Zn-Si anode delivers a superior CE of 99.6 % in 1000 cycles under 5 mA cm-2, and a stable cycle lifespan of 3600 h under 1 mA cm-2 with much lower polarization potential (42 mV), outperforming the symmetrical battery with pure Zn anode (455 h, 59 mV) and various previously reported strategies. Additionally, the effectiveness of Nano-Si layer is further proved in the Zn-Si/MnO2 battery, which presents a greatly improved capacity retention and cycling performance.

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