Electrospinning of carbon-coated MoO2 nanofibers with enhanced lithium-storage properties

Abstract

Novel carbon-coated MoO₂ nanofibers have been fabricated through a controlled route based on single-nozzle electrospinning, air stabilization, and reduction/carbonization processes. They are composed of both a uniform carbonaceous shell of 3 nm in thickness and a hierarchical core made of primary MoO₂ nanocrystal clusters of 20 nm in size. Importantly, the electrode made of such unique carbon-coated MoO₂ nanofibers exhibits a highly reversible capacity as high as 762.7 mAh g⁻¹ over 100 cycles. In contrast to the carbon-free MoO₂ particulates, the MoO₂ nanofibers, featuring both nanocrystal clusters and carbon coating, reveal a substantial improvement in electrochemical lithium-storage performances. This might benefit from the synergistic effect of the nanohybridization, relieving the volume effect during the repeated lithium insertion/extraction reactions and maintaining electrical connective integrity. It is expected that the present synthetic strategy can be extended to synthesize other nanostructured oxides with carbon coating for important energy storage and transfer applications.