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Carbonaceous materials are considered strong candidates as anode materials for sodium‐ion batteries (SIBs), which are expected to play an indispensable role in the carbon‐neutral era. Herein, novel braided porous carbon fibres (BPCFs) are prepared using the chemical vapour deposition (CVD) method. The BPCFs possess interwoven porous structures and abundant vacancies. The growth mechanism of the BPCFs can be attributed to the polycrystalline transformation of the nanoporous copper catalyst in the early stage of CVD process. Density functional theory calculations suggest that the Na+ adsorption energies of the mono‐vacancy edges of the BPCFs (−1.22 and −1.09 eV) are lower than that of an ideal graphene layer (−0.68 eV), clarifying in detail the adsorption‐dominated sodium storage mechanism. Hence, the BPCFs as an anode material present an outstanding discharge capacity of 401 mAh g−1 at 0.1 A g−1 after 500 cycles. Remarkably, this BPCFs anode, under high‐mass‐loading of 5 mg cm−2, shows excellent long‐term cycling ability with a reversible capacity of 201 mAh g−1 at 10 A g−1 over 1000 cycles. This study provided a novel strategy for the development of high‐performance carbonaceous materials for SIBs. [ABSTRACT FROM AUTHOR]

Long bundles up to several millimeters of aligned carbon nanofibers (CNFs) have been prepared by pyrolysis of a mixture of acetylene and ferrocene in a vertically installed quartz reactor by floating catalyst method. After a long period of reaction, the product of thick blocks closely adhered on the reactor wall was obtained. Field emission scanning electron microscopy (FESEM) verified that blocks were composed of aligned CNF bundles with a high purity that was attested by the means of X-ray diffraction (XRD) and thermal gravimetric (TG) analysis. The morphology and structure features of the CNFs were checked by transmission electron microscopy (TEM) and Raman spectroscopy, respectively. It was originally reported that aligned CNF bundles were synthesized by vertically floating catalyst method. [Copyright &y& Elsevier]