Terruzzi, P., Alburquenque, D., Saavedra, E., & Escrig, J. (2026). Magnetic properties of cobalt nanofibers synthesized via electrospinning and thermal treatment: Implications for nanoscale device applications. Chinese Journal of Physics. https://doi.org/10.1016/j.cjph.2026.02.008
Abstract: We report the synthesis of high-purity cobalt nanofibers (CoNFs) via electrospinning, followed by calcination and thermal reduction in a hydrogen-containing atmosphere. The resulting one-dimensional nanostructures exhibit an average diameter of approximately 130–140 nm while retaining a robust fibrous morphology. Structural and chemical characterizations using SEM, TEM, XRD, and EDS confirm the phase transformation from spinel-type Co3O4 to metallic cobalt, with a coexistence of FCC and HCP crystallographic phases. Magneto-optical Kerr effect (MOKE) measurements reveal clear ferromagnetic behavior with a coercivity of 20.4 mT.
Micromagnetic simulations capture the main features of the experimental hysteresis behavior and provide physical insight into the magnetization reversal process. A qualitative agreement between experimental observations and simulations is obtained for both isolated nanofibers and interacting nanofiber arrays, highlighting the role of geometry, phase coexistence, and magnetostatic coupling in governing the magnetic response. The simulations reveal a non-uniform magnetization reversal process characterized by skyrmion-like tubular magnetization configurations that are not topologically protected and arise from geometric confinement and magnetostatic effects rather than Dzyaloshinskii–Moriya interaction.
Residual oxide phases detected after thermal reduction and the use of a simplified micromagnetic model—neglecting thermal activation and fully realistic structural disorder—represent important limitations of the present study. Despite these constraints, the combined experimental–computational approach provides a physically grounded framework for understanding collective magnetization reversal in electrospun cobalt nanofiber networks, supporting their potential use in spintronic components, magnetic sensors, and magnetically actuated nanosystems.
Daniela Alburquenque
daniela.alburquenque@umayor.cl
