3D porous Sb-Co nanocomposites as advanced anodes for sodium-ion batteries and potassium-ion batteries

To tackle the issue of poor rate capability and cycle stability of Sb-based alloy anodes for sodium-ion batteries (SIBs) and potassium-ion batteries (PIBs), especially the abrupt capacity decay of Sb anode for PIBs, herein 3D porous structured Sb-Co nanocomposites are synthesized by a simple reduction precipitation and used as novel anode materials for SIBs and PIBs. The Sb-Co nanocomposite anode exhibits excellent rate capability and cycle performance. This anode for SIBs delivers a reversible capacity of 717.6 mAh at 60 mA g(-1) and a 377.8 mAh g(-1) reversible capacity at 6000 mA g(-1). Moreover, the Sb-Co nanocomposite anode for PIBs exhibits a reversible capacity of 402.7 mAh g(-1) after 100 cycles at 60 mA g(-1). Enhanced electrochemical performance of porous Sb-Co nanocomposites can be attributed to the synergistic effect of the Sb nanoparticles, 3D porous nanostructure and the incorporation of Co element. These results demonstrate that the Sb-Co nanocomposites are promising anode materials for SIBs and PIBs.