Ultra-Stable Zinc Metal Anodes Enabled by Uniform Zn Deposition on A Preferential Crystal Plane

The unsatisfactory electrochemical performance of Zn metal batteries (ZMBs) caused by uncontrollable Zn dendrite growth and detrimental parasitic reactions has significantly hindered their large-scale applications. Herein, periodic hemispherical structures with a preferential exposure of Cu (100) crystal plane are designed and obtained using facile photolithography, which is followed by wet etching treatment. An exposed zincophilic Cu (100) crystal plane with low nucleation barriers acts as the preferred deposition site to induce homogeneous Zn deposition. Additionally, the periodic hemispherical structure with an enlarged surface area not only suppresses the Zn dendrite growth by reducing the local current density, but also synergistically buffers the volume expansion during the cycling process. As a result, the as-prepared faceted Cu hemispherical electrodes achieve ultra-stable Coulombic efficiency of over 99.9% for 1500 cycles at a current density of 5 mA cm-2. This work has significant potential for the rational design of dendrite-free Zn anodes to boost their potential for practical applications. Periodic 3D hemispherical structured Cu foil with preferential exposure of the Cu (100) crystal plane are designed and obtained using a sequential photolithography-wet chemistry method. The 3D Cu foil lowers the Zn nucleation barriers, reduces the local current density and buffers the volume expansion during the cycling process, which induces homogeneous Zn deposition and achieves prolonged cycle life.image