Supersonic solution blowing: a novel approach to producing self-supported carbon–silica microporous nanofibers for Li-ion battery anodes

The development of self-supporting electrodes, which are binder-, and additives-free, is essential for increased performance and practical applications of lithium-ion batteries (LIBs). With this aim, we report here the synthesis of carbon nanofiber (CNF) composites containing silica (SiO₂) nanoparticles via Supersonic Solution Blowing (SSB) as self-supporting electrodes of LIBs. Nanofibers with average diameter in the 86–271 nm range, and specific surface area (SSA) in the 619–1981 m²/g were obtained. SiO₂ content altered not only the diameter and the SSA, but also the pore-size distribution. A tri-modal pore-size distribution pattern was obtained for all specimens. Used as a self-supporting anode material for LIBs, carbon nanofiber-based composite electrodes achieved high reversible capacity, high-rate capacity, and superior cyclic stability (305–444 mAh g⁻¹ at 0.1 A g⁻¹ after 200 cycles), at the Coulombic efficiencies of 97−99%. Lastly, enhanced capacity can be attributed to the addition of SiO₂ nanoparticles up to 2.5%. However, for higher silica content, the loss in performance can be attributed to an increase in the mean nanofiber diameter and a drastic reduction in SSA and porosity caused by the presence of nanoparticles.