Boosting Ultrafast Lithium Storage Capability of Hierarchical Core/Shell Constructed Carbon Nanofiber/3D Interconnected Hybrid Network with Nanocarbon and FTO Nanoparticle Heterostructures

The aim of the study involves accelerating ultrafast electrochemical behavior of lithium-ion batteries (LIBs) by proposing hierarchical core/shell heterostructure of carbon nanofiber (CNF)/3D interconnected hybrid network with nanocarbon and fluorine-doped tin oxide (FTO) nanoparticles (NPs) via a one-pot process of horizontal ultrasonic spray pyrolysis deposition. This is constructed via a pyrolysis reaction of ketjen black forming 3D interconnected FTO NPs covered with nanocarbon network on CNF. It offers fast electrical conductivity to the overall electrode with improved Li ion diffusion due to decreased size effect and relaxed structural variation of FTO NPs via nanocarbon network, leading to high discharge capacity (868.7 mAh g⁻¹ after 100 cycles) at 100 mA g⁻¹ and superior rate capability. Nevertheless, at extremely high current density (2000 mA g⁻¹), significant ultrafast electrochemical performances with reversible discharge capacity (444.4 mAh g⁻¹) and long-term cycling retention (89.9% after 500 cycles) are noted. This is attributed to the novel effects of 3D interconnected hybrid network accelerating receptive capacity of Li ions into the FTO NPs via nanocarbon network, delivery of formed Li ions and electrons by hybrid network with FTO NP and nanocarbon, and prevention of FTO NP pulverization from CNFs via nanocarbon network. Therefore, the proposed heterostructure holds significant promise for effective development of ultrafast anode material for enhancing the practical applications of LIBs.