Tubular nanostructured Co3O4@N-containing carbon nanofibers to tune the surface structure for efficient electrochemical capacitors

Abstract

BackgroundAlthough N-rich electrode materials have good capacitive performance, further exploration of more efficient and straightforward methods to produce nanoporous carbon materials with a high heteroatom content remains challenging. MethodsTubular nanostructured Co3O4@N containing carbon nanofibers (PPMCoU(10)) are fabricated by coaxial electrospinning to improve the overall electrochemical performance. Significant findingsThe PPMCoU(10) electrode shows a high specific capacitance (193 Fg−1 at 1 mAcm−2), good rate capability (88% capacity retention at 20 mAcm−2), high energy density (24.5 Whkg−1 at 400 Wkg−1), and good cycling stability (only 8.0% loss after 10,000 cycles at 1 mAcm−2). The enhanced stored charge capacity of the PPMCoU(10) electrode is attributed to the synergy of high microporosity with a high surface area, tubular nanostructure, low crystallinity of Co3O4, many oxygen vacancies, and electrochemically active nitrogen atoms.