Vertical Crystal Plane Matching between AgZn (002) and Zn (002) Achieving a Dendrite-Free Zinc Anode.

Metallic zinc anodes in zinc-ion batteries suffer from problematic Zn dendrite chemistry. Previous works have shown that preferred-orientation crystal planes can help dendrite-free metal anodes. This work reports a nanothickness (≈570 nm) AgZn  coating to regulate the Zn growth. First, AgZn @Zn anode avoids the problem, in Ag@Zn anode, that the rate of electrochemical Ag-Zn alloying is slower than that of Zn dendrites growth. Batteries life increased from 112 h (pure Zn) and 932 h (Ag@Zn) to 1360 h (AgZn @Zn) at 2 mA cm  and 1 mAh cm . Then, plasma sputtering can remove nonconductive ZnO and improve Zn-ion affinity, which brings a longer life for AuZn @Zn (423 h), CuZn @Zn (385 h), and AgZn @Zn (1150 h) than pure Zn (93 h) at 1 mAh cm . More importantly, AgZn (002) has a high matching with the Zn (002), which can guide ordered Zn epitaxial deposition, thereby achieving dense and dendrite-free Zn growth. This work clearly captures the fascinating structure of the densely stacked Zn layers on the AgZn  layer. This strategy not only improves the performance of zinc-ion batteries greatly but will also help one understand the matching mechanism of the (002) vertical crystal plane.