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One-dimensional hierarchical porous carbon nanofibers (CNFs) embedded with Co 3 O 4 nanoparticles in a hollow channel (PPMCo) are fabricated by coaxial electrospinning followed by thermal treatment. The degree to which the CNF surface is exposed to Co 3 O 4 nanoparticles was controlled by the cobalt(II) acetate concentration. The well-controlled structure of PPMCo with porous structure, heteroatoms, and amorphous Co 3 O 4 nanoparticles provided fast ion transport and large reaction surface area, resulting in effective ion migration to the active site and a high rate capacity of the electrode. Benefitting from the unique structure, the PPMCo supercapacitor electrodes displays a high specific capacitance of 188 Fg−1 at 1 mAcm−2, rate capability of 82% when the current density is increased from 1 to 20 mAcm−2, and cycling stability of 93% for 10,000 cycles. The good capacitive performance of the PPMCo electrode is attributed to the synergistic effect of the hierarchical porosity, electroactive material of Co 3 O 4 , high effective surface area, and polar effects by heteroatoms. [Display omitted] • Hierarchical porous CNF embedded with Co3O4 was prepared by coaxial electrospinning. • The degree of CNF exposed to Co3O4 was controlled by the Co(OAc)2 concentration. • The hollow core of the core part provides a fast electron transport channel. • Amorphous Co3O4 helps transport ions by reducing the charge transfer resistance. • The heteroatom functional groups on the carbon surface enhance the pseudocapacitance. [ABSTRACT FROM AUTHOR]