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[Display omitted] • Hollow N -rich multilayered CNFs are prepared by sequential electrospinning. • The top-layer PAN/urea-based CNF acts as charge storage and pseudocapacitance. • The interlayer PMMA-based CNFs with tubular structure promote charge transport. • The bottom layer of PAN-based CNFs with numerous micropores provides charge storage. N -rich multilayered carbon nanofibers with hollow channels (PPMPN) are fabricated to fully utilize the mesopores, micropores, and nitrogen-functional groups of carbon nanofibers (CNFs) for superior electrochemical properties. Among all composites, the PPMPN(10) exhibits high specific surface area (570 m2g−1) with mesopore volume fraction (42%) and rich surface functionalities (∼7.25at% nitrogen and ∼ 16.1at% oxygen), helping to improve electrochemical performance. The performance of the symmetric supercapacitor of the PPMPN was significantly improved in terms of its specific capacitance of 189 Fg−1 at 1 mAcm−2, good retention of 80% (when the current density is increased from 1 to 20 mAcm−2), energy density of 23.5 Whkg−1 at a power density of 400 Wkg−1, and cycling stability of 94% for 10,000 cycles. The top layer plays a role in charge storage/transport by increasing electrical conductivity due to N -functional groups. The intermediate layer with tubular 1D nanostructures enhances the diffusion of electrolyte ions even at higher current densities. The bottom layer composed of numerous micropores serves as a charge storage layer. Therefore, in the multilayer CNF, the micropores/mesopores and N -functional properties of each layer do not interfere with each other, and the advantages of the factors of each layer are maximized in the electrochemical properties. [ABSTRACT FROM AUTHOR]

Fabricating continuous porous carbon nanofibers (CNFs) based on biomass materials still remains challenging for current supercapacitors (SCs) results from the limitation of carbon yield and molecular flexibility. In this work, P and N dual-doped 1D porous carbon nanofibers (PNF) are prepared through a controllable way by electrospinning phytic acid solution of chitosan (CS)/ polyvinylpyrrolidone (PVP) with subsequent crucial segmented carbonization. Due to the ultra-high specific surface area, extremely low charge transfer resistance, and the contribution of N, P dual doping to pseudocapacitors, the obtained PNF exhibits the highest specific capacitance of 358.7 F g−1 at a current density of 1 A g−1. More notably, a symmetrical SC assembled by PNF achieves an outstanding capacitance of 94 F g−1 at a current density of 0.5 A g−1, and a high energy density of 13.1 W h kg−1 at a power density of 248 W kg−1, furthermore, a high capacitance retention of 87.5% is performed after 10,000 cycles. It is firmly believed that the research on the preparation method and performance of carbon nanofibers involved in this article is of profound inspiration for mobile power sources. 1D dendritic N,P dual-coping hierarchical porous carbon nanofibers. Unlabelled Image • 1D dendritic N,P dual-coping carbon nanofibers are prepared via a facile way from chitosan nanofibers. • The CNF samples show rich heteroatom doping and excellent hierarchical porous structure. • The network structure of dendrite carbon nanofibers has very low charge transfer resistance. • The CNF samples exhibits excellent specific capacitance and cycle stability. • The symmetric SC achieves an ascendant balance in energy and power density. [ABSTRACT FROM AUTHOR]

A new type of PAN/phenylsilane-based CNF (PPSCD) composite with inclusion complex (IC) is prepared by one-step electrospinning for high-performance electrode materials for supercapacitors. All three cyclodextrin phases (α-CD, β-CD and γ-CD) exhibit different capabilities for the formation of ICs that depend on the size/shape match and binding force between the host CD cavity and the guest molecule of phenylsilane (PS). The effect of the stronger binding and greater interaction of PS in the cavity of α-CD on the morphology and structural properties of the electrospun CNFs are investigated by using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and 29Si CP-MAS NMR. The inclusion of small PS molecules is more selective in α-CD, possibly due to stronger binding and greater interaction of PS in the cavity as compared to β- and γ-CD. The PPSα-CD electrode demonstrates superior specific capacitance (173 Fg−1 at a current density of 1 mAcm−2) and high energy density (22.0–8.0 Whkg−1 at power densities ranging from 400 to 10,000 Wk−1) in an aqueous solution. Therefore, the highly conductive PPSα-CD composite provides efficient transport of electrolyte ions and low resistance for charge diffusion in the electrolyte, thereby yielding good capacitive behavior. Unlabelled Image • A new type of PPSCD with ICs is fabricated by one-step electrospinning. • The larger γ-CD is less interactive with PS, so more silica is formed. • PPSγ-CD exhibits low conductivity due to the insulating nature of the silica particles. • The inclusion of PS is more selective in α-CD due to size matching. • Highly conductive and porous PPSα-CD is applied to high-performance supercapacitors. [ABSTRACT FROM AUTHOR]

Hierarchical MnO 2 arrays with nanowire-built multitripod structures were successfully deposited on porous carbon nanofibers (PCNFs) by a simple electrospinning followed by redox reaction. The unique multitripod architectures of MnO 2 nanowire arrays pave well-developed network for rapid electron transfer and improve entire mechanical stability. Additionally, this hierarchical porosity of PCNFs substrate is favorable for guaranteeing sufficient penetration of electrolyte ions. Benefiting from all synergistic effects, the as-prepared MnO 2 /PCNFs flexible electrode exhibits a specific capacitance of 512 F g−1 at 1 mA cm−2, a super rate capability (460 F g−1 at 50 mA cm−2) and cycling stability. Moreover, a fabricated symmetrical coin device delivers a specific energy density of 51.2 Wh kg−1 maintaining the power density of 585.3 W kg−1 and still keep 15.2 Wh kg−1 even at the ultra-high power density of 59.7 kW kg−1. These hierarchical MnO 2 arrays comprising unique nanowire-built multitripod structures show potential prospects for future advanced energy storage devices. Unlabelled Image • Hierarchical MnO 2 nanowire arrays consisting of multitrpod structures grown on porous carbon nanofibers (PCNFs) were successfully prepared by adopting a simple electrospinning and redox reaction. • The unique tripod structure of MnO 2 nanowire array facilitates electron transfer and improves overall mechanical stability. • Pre-inserted the K+ cations originating from K source during preparation procedures play a key role in enhancing capacitance and stability performance. [ABSTRACT FROM AUTHOR]