Yolk‐Shell Sb₂S₃@C Hollow Microspheres with Controllable Interiors for High Space Utilization and Structural Stability of Na‐Storage

Abstract Structural stability, space utilization and appropriate working potentials are the most crucial parameters for evaluating the practical application of various electrode materials in sodium‐ion batteries (SIBs). To obtain a high‐performance anode material for SIBs, a novel Sb₂S₃@carbon composite with unique and controllable hollow microspherical structures is prepared through a facile and large‐scalable approach. By adjusting the precursor concentrations, yolk‐shell and simple hollow Sb₂S₃@carbon microspheres are obtained respectively. The formation mechanisms of different hollow interiors are discussed. It is found that simple hollow Sb₂S₃@carbon microspheres tend to collapse into fragments when being used as the anode materials of SIBs, leading to severe electrolyte decomposition and high charge‐transfer resistance. In contrast, yolk‐shell Sb₂S₃@carbon not only possesses high space utilization, but also preserves the microspherical structure well after long‐term sodiation/desodiation reactions, endowing it with high capacity, good cycling stability, and fast charge/discharge capability.