Construction of a self-supported dendrite-free zinc anode for high-performance zinc-air batteries

Zinc-anode-based batteries are widely used in energy storage devices due to their low cost, high-energy density, and environmental friendliness. However, the fatal dendrite growth of the zinc anode during cyclic plating and stripping processes severely affects the service life of the batteries. Herein, a ZIF-8-derived Zn-ZnO@C-550 anode, i.e. ZnO nanoarrays grown in situ on the surface of zinc foil via chemical deposition followed by hydrothermal synthesis and annealing, is designed for zinc-air batteries. With this prepared self-supported anode, the assembled zinc-air battery exhibits excellent discharge performance (995.77 mA h) compared to the same size of zinc foil, and remarkable cycling performance (more than 1200 cycles at a large current density of 10 mA cm(-2)) with dendrite growth being suppressed. The superior anti-dendritic properties of the fabricated Zn-ZnO@C-550 anode can be attributed to the highly ordered array structure of the Zn anode, which allows a homogeneous zinc ion concentration to avoid the growth of metallic zinc clusters, as confirmed by a simulation of the electrode current density distribution. The reversibility of Zn2+ plating/stripping in this work provides a promising strategy for preparing a dendrite-free metal anode of these Zn-related batteries.