ZIF-derived Cobalt-containing N-doped Carbon Coated SiOx Nanoparticles for Superior Lithium Storage

N-doped carbon encapsulated SiOx and Co nanoparticles are synthesized by the calcination of ZIF-67 coated SiOx nanoparticles. This composite associates the good electrochemical conductivity and the superior accommodation to volume change from N-doped carbon and Co with SiOx nanoparticles, exhibiting the improved cycle and rate performances for lithium storage. It retains a capacity of 1044 mAh g-1 over 150 cycles at 1.5 A g-1, outperforming those without Co or N-doped carbon. It well confirms the contributions of Co and N-doped carbon to the electrochemical properties of SiOx. Even after 350 cycles at 1.0 A g-1, this composite none the less delivers a capacity of 900 mAh g-1. If it is coupled with LiFePO4, the full cells show a stable cycling, indicating the promising application of this composite.