Synthesis and characteristics of silica-coated carbon nanofibers on electroplated Co-Ni/C-fiber textiles

In this study, carbon nanofibers (CNFs) were synthesized by chemical vapor deposition (CVD) to Co-Ni electroplated on C-fiber textiles. The synthesized CNFs were coated with a SiO₂ layer through the hydrolysis of tetraethyl orthosilicate (TEOS). The characteristics of the CNFs were analyzed by SEM, EDS, XPS, and Raman spectroscopy. The morphology and characteristics of the SiO₂-CNFs composite were investigated using TEM and XPS. It was thus verified that the CNFs were synthesized with a diameter of 30-40 nm and the SiO₂ layer was uniformly coated to a thickness of 10 nm onto their surfaces. The electrochemical characteristics of the CNFs and the SiO₂-CNFs composite were investigated using coin cell by galvanostatic charge-discharge. The as-synthesized CNFs and SiO₂-CNFs composite were directly employed as anode materials without any binder. The CNFs had a discharge capacity of 258 mAhg^-1 at the initial cycle with a retention rate of 95% after 30 cycles. The discharge capacity of the SiO₂-CNFs composite was 1,486 mAhg^-1 with a retention rate of 47%, which was greater than that of the CNFs.