▎ 摘 要
A three-dimensional (3D) silicon/carbon nanofiber-graphene (Si/CNF-G) nanostructure is constructed by encapsulating Si nanoparticles in carbon nanofibers, followed by wrapping with graphene nanosheets. The graphene-wrapped silicon/carbon nanofibers hybrids have the advantages of good dispersion of Si nanoparticles inside the 3D carbon network. Meanwhile, the 3D carbon network can also act as a current collector to promote charge transfer and maintain stable electrical contact of the Si nanoparticles. The resulting Si/CNF-G composites can be used directly as binder-free electrodes. The composite exhibits a stable capacity retention and a reversible capacity of 878 mAhg(-1) for up to 100 cycles, along with a high rate capacity (514 mAhg(-1) at 5.0 Ag-1). These results provide a promising research platform for fabricating stable electrodes with improved electrochemical performance.