Structure Engineering by Picosecond Laser Lithography Boosts Highly Reversible Zn Anode

Abstract

The practical application of aqueous zinc ion batteries (AZIBs) is impeded by the instability of the Zn anode|electrolyte interface, including dendrite growth, hydrogen evolution reaction (HER), and corrosion. Herein, the periodical micro-nano structure is constructed on the surface of Zn anode through picosecond laser lithography (PLL) technology. This micro-nano surface structure is conductive to obtain hydrophobicity for diminishing direct contact between the electrolyte and Zn anode, enhancing the corrosion resistance of the Zn anode. Simultaneously, the low surface energy and reconstructed electric field are achieved through laser-induced texture microstructure, leading to the oriented Zn²⁺ deposition along the (002) plane. As a result, the lower electrochemical polarization and long cycling stability of 1400 h for Zn||Zn symmetric cell is achieved at 4 mA cm⁻² and 2 mAh cm⁻². The average coulombic efficiency (CE) of the Zn||Cu cell is enhanced to 99.83% at 2 mA cm⁻², while the Zn||MnO₂ cell delivers a capacity retention of 68.7% after 600 cycles at 1 A g⁻¹. Consequently, the advantages of micro-nano structure can highlight the importance of surface structure design for the development of stable Zn anode.