High-kinetic and stable antimony anode enabled by tuning coordination environment for ultrafast aqueous energy storage

Abstract

Antimony (Sb) with stripping/plating behavior is attractive as anode material for aqueous energy storage. However, it suffers from unfavorable ion diffusion and de-solvation issues due to special coordination environment of Sb(III), resulting in poor rate capability. Herein, we regulate the coordination environment by introducing high-affinity Cl− ligands to achieve high-kinetic and reversible Sb stripping/plating. It enables faster diffusion kinetics and lower de-solvation energy barrier to promote the manageable nucleation and deposition of Sb even at ultrahigh current densities on various of collectors (carbon felt, Ti foil and F-doped tin oxide, etc). Notably, the Sb anode on carbon felt substrate delivers coulombic efficiency of 97.0%, high-rate capability (98.4% capacity retention from 20 to 500 mA cm−2 or 250 C) and satisfactory stability. The as-assembled CoxNiy(OH)z//Sb battery also provides outstanding rate capability and durability. This work provides new inspiration for developing ultrafast Sb-based aqueous energy storage.