Surface-Preferred Crystal Plane for a Stable and Reversible Zinc Anode.

Aqueous zinc-ion batteries are largely restricted by the unsatisfactory performance of zinc (Zn) anodes, including their poor stability and irreversibility. In particular, the mechanism behind the electrochemical contrast caused by the surface crystal plane, which is a decisive factor of the electrochemical characteristics of the hostless Zn anode, is still relatively indistinct. Hence, new insight into a novel anode with a surface-preferred (002) crystal plane is provided. The interfacial reaction and morphology evolution are revealed by theoretical analysis and post-mortem/operando experimental techniques, indicating that Zn anodes with more exposed (002) basal planes exhibit free dendrites, no by-products, and weak hydrogen evolution, in sharp contrast to the (100) plane. These features benefit the Zn (002) anode by enabling a long cyclic life of more than 500 h and a high average coulombic efficiency of 97.71% for symmetric batteries, along with delivering long cycling stability and reversibility with life spans of over 2000 cycles for full batteries. This work provides new insights into the design of high-performance Zn anodes for large-scale energy storage and can potentially be applied to other metal anodes suffering from instability and irreversibility.