A novel and fast method to prepare a Cu-supported α-Sb₂S₃@CuSbS₂binder-free electrode for sodium-ion batteries

Antimony sulfide (Sb2S3) is a promising anode material for sodium-ion batteries due to its low cost and high theoretical specific capacity. However, poor stability and a complex preparation process limit its large-scale application. Herein, we prepare a binder-free composite electrode composed of amorphous (α-) Sb2S3 and copper antimony sulfide (CuSbS2) through a simple closed-space sublimation (CSS) method. When applied as the anode in sodium-ion batteries, the α-Sb2S3@CuSbS2 electrode exhibits excellent performance with a high discharge capacity of 506.7 mA h g-1 at a current density of 50 mA g-1 after 50 cycles. The satisfactory electrochemical performance could be ascribed to the α-Sb2S3-CuSbS2 composite structure and binder-free electrode architecture, which not only retain the structural stability of the electrode but also improve the electrical conductivity. Consequently, CSS, as a scalable and environmentally friendly method, can produce a binder-free electrode in just a few minutes, demonstrating its great potential in the industrial production of sodium-ion batteries. This study may open an avenue to preparing binder-free commercial electrodes.