A three-dimensional macroporous antimony@carbon composite as a high-performance anode material for potassium-ion batteries

Abstract

Potassium-ion batteries (KIBs) are considered important substitutes for lithium-ion batteries (LIBs) owing to the abundance of K resources. Herein, a novel three-dimensional macroporous antimony@carbon composite (Sb@C-3DP) is fabricated by a simple KCl template method with a single bi-functional precursor potassium antimony tartrate. The Sb@C-3DP electrode delivers an excellent rate capability (286 mA h g⁻¹ at 1 A g⁻¹) and remarkable reversible capacity (516 mA h g⁻¹ at a low current density of 0.05 A g⁻¹). Moreover, an outstanding long-term cycling stability (97% capacity retention after 260 cycles) is also achieved, which is benefited from the unique microstructure that can accommodate the huge volumetric change of Sb during depotassiation and potassiation processes. A full cell constructed by coupling Sb@C-3DP with a Prussian blue cathode exhibits a high energy density (197.6 W h kg⁻¹) and power density (2067.9 W kg⁻¹).