Liquid Metal-Skinned Zn Powder Anodes Enabled by Capillary Suspension

Abstract

Zinc (Zn) powder-based anodes have garnered considerable attention as viable alternatives to their conventional Zn foil-based counterparts. However, challenges arising from undesirable interfacial side reactions and dendritic Zn growth hinder their practical implementation. Here, we present a class of liquid metal-skinned Zn (LSZ) powder anodes enabled by capillary suspension. The capillary suspension strategy can overcome the miscibility of liquid metal with other components, resulting in the self-standing and uniform LSZ powder anode. The nanothick eutectic gallium-indium (EGaIn) skin layer on Zn powders facilitated the horizontal growth of Zn along the (002) plane and mitigated Zn corrosion and hydrogen evolution reaction. Consequently, a full cell (V2O5 cathode parallel to LSZ powder anode) exhibited a stable capacity retention per cycle of 99.99% over 2000 cycles at a fast current rate of 1 A g(-1), outperforming those of previously reported aqueous Zn full cells.