N-Doped Hollow Multichannel Carbon Nanofibers Encased in Fe₃C for Lithium-Ion Storage

Abstract

In advancing lithium-ion batteries to achieve high energy densities, prolonged cycling lifespan, and enhanced charging rates, electrode materials with high specific capacities play a crucial role. In this study, we have developed a porous carbon substrate using coaxial electrostatic spinning to enhance the electrochemical properties of the carbon-based anode. This porous structure exposes numerous active sites for Li + ions and reduces the Li + /e − transport pathway, thereby improving the kinetics of Li + /ion and electron transfer. The symbiotic interaction between N and Fe 3 C nanoparticles facilitates the formation of hollow channels and dual conductive pathways. These Fe 3 C nanoparticles, along with hollow carbon nanofibers, enhance long-term cycling stability at room temperature, promote the formation of stable SEI layers, and improve interfacial compatibility. The Fe 3 C hollow multichannel carbon fibers (Fe 3 C/HMCFs) were subjected to analysis using a magnetic measurement system to investigate the charge transfer phenomenon. The observed charge transfer behavior confirms the conductivity of the magnetic Fe 3 C materials. These Fe 3 C/HMCFs exhibit favorable electrochemical characteristics, including an initial capacity of 1130 mAh g −1 at a current density of 2 A g −1 and a second charge/discharge capacity of 706 mAh g −1 .