Advances in the Interfacial Engineering of Carbon Nanofibers via Heteroatom Doping for Dendrite-Free, Stable Lithium-Metal Anodes

Lithium-metal anodes offer exceptional theoretical capacity and the lowest electrochemical potential, but their practical use is limited by dendrite growth, unstable SEI formation, and large volume fluctuations. Carbon nanofibers (CNFs), with their low weight, high conductivity, and tunable structures, serve as effective hosts for regulating lithium deposition. Heteroatom doping further enhances lithiophilicity and interfacial stability: nitrogen creates abundant nucleation sites, oxygen and sulfur increase surface polarity and strengthen the SEI, and fluorine facilitates LiF-rich interphases for dendrite-free growth. Multi-element doping can also provide synergistic improvements in Coulombic efficiency and cycling stability. Despite these advances, challenges remain, including electrolyte consumption in high-surface-area structures, nonuniform dopant distribution, and potential degradation of CNF properties at high doping levels. This article summarizes recent progress in heteroatom-doped CNFs for lithium-metal anodes and outlines key limitations and future directions toward scalable, high-performance lithium-metal batteries.