Synthesis of oxidized acetylene black/sulfur@Nd₂O₃ composite as cathode materials for lithium-sulfur batteries

Abstract

Lithium-sulfur batteries with a high theoretical specific capacity of 1672 mAh g⁻¹ have been paid tremendous attention to serving as energy storage system. However, the dissolution of polysulfide intermediates could result in poor cycling stability of lithium-sulfur batteries and hinder its practical application. In this work, a novel neodymium oxide (Nd₂O₃) nanoparticle doped the oxidized-acetylene black/sulfur (H-AB/S@Nd₂O₃) composite has been synthesized through in situ chemical deposition and solvent dispersion. The as-oxidized acetylene black is served as the conductive carbon scaffold and the as-prepared Nd₂O₃ nanoparticles, acting as the additive of the H-AB/S composite, can effectively alleviate the loss of polysulfides. As a result, the sulfur-based composite with 5 wt% Nd₂O₃ nanoparticles exhibits the high specific capacity and excellent cycling stability. The initial discharge capacity is 1171 mAh g⁻¹ at 0.1 C and remains at 748 mAh g⁻¹ after 200 cycles with a capacity retention of 63.9%. Even at a high current density of 1 C, the electrode delivers a maximum discharge capacity of 700 mAh g⁻¹after activation and the capacity retention is approximately 68% after 200 cycles.