Stibnite (Sb2S3) and its amorphous composite as dual electrodes for rechargeable lithium batteries

Abstract

Orthorhombic Sb₂S₃ (stibnite) and its amorphous Sb₂S₃/C composite were synthesized by solid-state routes, such as heat treatment and high energy mechanical milling (HEMM). X-ray diffraction, X-ray photoelectron spectroscopy and high resolution transmission electron microscopy confirmed that the amorphous Sb₂S₃/C composite was composed of amorphous Sb₂S₃ phases distributed uniformly within an amorphous carbon matrix. The electrochemical reaction mechanism of amorphous Sb₂S₃/C with Li was examined by extended X-ray absorption fine structure analyses. The fabricated amorphous Sb₂S₃/C composite electrode showed excellent electrochemical properties, such as a high energy density (1st charge: 757 mAh g⁻¹), long cyclability (ca. 600 mAh g⁻¹ over 100 cycles), and good initial Coulombic efficiency (ca. 85%). When tested within various voltage windows, the amorphous Sb₂S₃/C composite electrode was found to be suitable for use as a dual electrodes, such as the anode in Li-ion batteries or the cathode in Li/S batteries.