Fabrication of carbon nanofibers with Si nanoparticle-stuffed cylindrical multi-channels via coaxial electrospinning and their anodic performance

This paper reports on a fabrication method to manufacture cylindrically multi-channeled hollow carbon nanofibers (mcHCNFs). Polyacrylonitrile nanofibers with cylindrical multi-cores of poly(styrene-co-acrylontitrile) (SAN) were first electrospun using a specific nozzle and subsequently heat-treated, leaving vacant or silicon (Si)-encapsulated mcHCNFs. The latter was obtained by dispersing Si nanoparticles in the SAN solution. Investigations into the morphologies, microstructures, and material compositions of the resulting mcHCNFs demonstrated that Si-encapsulated multi-channels were formed in a controlled, uniform manner. The multi-channel effects were evaluated by characterizing the anodic properties of Si-encapsulated mcHCNFs using galvanostatic charge-discharge tests. More contact between the Si nanoparticles and the carbon shell in the Si-encapsulated mcHCNFs brought about improved discharge capacity and capacity retention.