Design and Synthesis of Sb‐Doped CuS@C Hollow Nanocubes as Efficient Anode Materials for Sodium‐Ion Battery

Abstract Copper sulfide has received widespread attention for application as anode materials in sodium‐ion batteries due to their potent capabilitiess and eco‐friendly properties. However, it is a challenge to achieve a high rate capability and long cycle stability owing to the heterogeneous transfer of sodium ions during charge‐discharge, the interior poor electron conductivity and repeated volumetric expansion of copper sulfide. In this study, Sb‐doped copper sulfide hollow nanocubes coated with carbon shells (Sb‐CuS@C) was designed and constructed as anode nanomaterials in sodium‐ion batteries. Thanks to the intrinsic good electron conductivity and chemical stability of carbon shells, Sb‐CuS@C possesses a higher overall electron transfer as anode material, avoids agglomeration and structural destruction during the cycling. As a result, the synthesized Sb‐CuS@C achieved an excellent reversible capacity of 595 mA h g −1 after 100 cycles at 0.5 A g −1 and a good rate capability of 340 mA h g −1 at a higher 10 A g −1 . DFT calculations clarify that the uniformly doped Sb would act as active sodiophilic nucleation sites to help adsorbing sodium‐ion during discharging and leading uniform sodium deposition. This work provides a new insight into the structural and componential modification for common transition‐metal sulfides towards application as anode materials in sodium‐ion battery.