Constructing a well-wettable interface on a three-dimensional copper foam host with reinforced copper nanowires to stabilize zinc metal anodes

Abstract

Metallic zinc (Zn), with high safety, low cost, and environmental friendliness, is deemed a promising anode for aqueous zinc-ion batteries. However, the practical application of Zn anode is still impeded by the growth of dendrites during the Zn plating/stripping process. Designing three-dimensional host material as the substrate is an effective approach to enhance the highly reversible plating/stripping behavior of the Zn anode. In this study, Cu nanowire-decorated Cu foam (Cu NW@Cu foam) with good wettability and zinc affinity was fabricated to enhance the reversibility of electroplating/electrostripping. It was found that the Cu NW@Cu foam host cannot only offer extra zincophilic nucleation sites by increasing the surface area but also guide a uniform ion distribution due to a capillary-like effect induced by the arrangement of numerous copper nanowires. As a result, the Cu NW@Cu foam as a well-wettable and zincophilic host shows a mosslike dendrite-free plating/stripping process with a small nucleation overpotential (19.5 mV) and an ultra-stable lifespan of 3000 h at 1 mA cm⁻² and 1 mA h cm⁻² in zinc symmetrical batteries. Moreover, the assembled full-cell with Zn@Cu NW@Cu foam as the anode and α-MnO₂ nanowire as the cathode delivered a stable discharge specific capacity of 181.8 mA h g⁻¹ at 2 A g⁻¹ over 3000 cycles. This study may provide a reliable strategy for designing dendrite-free high-performance zinc host materials with highly wetting interfaces.