Enhanced cycling properties of carbon-coated SnO₂-Co₃O₄ composite nanowires for lithium-ion batteries

Carbon-coated SnO₂-Co₃O₄ composite nanowires (NWs) are synthesized to improve the cycling properties of lithium-ion batteries, using electrospinning followed by carbonization using a dopamine precursor. These carbon-coated composite NWs show excellent capacity retention (∼542 mAh/g; 50 cycles) compared to bare SnO₂ NWs (∼101 mAh/g; 50 cycles) and SnO₂-Co₃O₄ composite NWs (∼323 mAh/g; 50 cycles). The performance improvement is due to the combined effects of the composite structure of SnO₂ and Co₃O₄ producing the enhanced capacity retention in the NW core region and the carbon coating in the shell region hindering large volume expansion-contraction of the electrode.