A Thin and Uniform Fluoride-Based Artificial Interphase for the Zinc Metal Anode Enabling Reversible Zn/MnO2 Batteries

Zn batteries have recently become of great interest as energy storage devices. However, their lifespan is limited by irreversible processes at the Zn anodes owing to side reactions and dendrite growth in a mild pH electrolyte. Herein, an artificial ZnF2 layer on the Zn metal anode surface is developed to address these issues. Modeling results suggest that ZnF2 can allow insertion of Zn2+ and offers diffusion channels for the transport to/from the Zn anode via an interstitial diffusion mechanism. The artificial layer suppresses dendrite growth by guiding the Zn plating/stripping underneath the layer, thus enhancing the electrochemical performance of the anode as demonstrated by the Zn-ZnF2/MnO2 full cell. The Zn anode with this artificial layer sustains long-term cycling (more than 700 h) at an areal capacity of 0.5 mAh cm(-2), and the Zn-ZnF2/MnO2 full cells achieve a capacity retention of 89% after 3000 cycles.

Automated summary

By developing an artificial ZnF2 layer on the surface of Zn metal anode, researchers have successfully addressed the limitation of zinc batteries' lifespan. This artificial layer suppresses dendrite growth and facilitates zinc insertion and transport through an interstitial diffusion mechanism. This improvement has been demonstrated by the long-term cycling and high capacity retention achieved by zinc-zincF2/MnO2 full cells.