A selenium disulfide-impregnated hollow carbon sphere composite as a cathode material for lithium-ion batteries

Abstract

A selenium disulfide-impregnated hollow carbon sphere composite was prepared as the cathode material for lithium-ion batteries. The morphology, composition, and structure of the as-synthesized composite were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and the Brunauer-Emmett- Teller (BET) technique. It was found that uniform monodispersive hollow carbon spheres can be synthesized by the template method combined with chemical polymerization. The diameter of the spheres is about 500 nm and the thickness of their wall is about 30 nm. Furthermore, a selenium disulfide-impregnated hollow carbon sphere composite can be achieved by the melting-diffusion method. The electrochemical performance of the as-synthesized composite as a cathode material for lithium-ion batteries was also investigated. Compared with the pristine bulk SeS2 material, the SeS2@HCS composite exhibits higher initial discharge capacity (956 mAh∙ g-1 at a current density of 100 mA∙g-1), longer cycle life (200 cycles at a current density of 100 mA∙g-1), and better rate performance. The results indicate that this composite can be considered as a promising candidate for the cathode material of lithium-ion batteries.