Rational Synthesis of Hierarchical Bramble‐Shaped Co/CoO Nanofibers with Enhanced Lithium Storage Properties

The hierarchical bramble‐shaped Co/CoO nanofibers have been successfully synthesized by rational and delicate electrospinning/post‐thermal treatment. The metal Co thorns are distributed homogeneously on the surface of CoO nanofiber matrix. The hierarchical Co/CoO nanofibers manifest the remarkable lithium storage performance with excellent rechargeable stability (charge/discharge capacity of 794.2/794.4 mAh g−1 after 200 cycles) and improved rate capacities (discharge capacity of 285.4 mAh g−1 at the high rate of 10 C, 1 C=716 mA g−1), which could be attributed to the advantage of unique hierarchical structures to keep the structural stability and hold the large specific surface area (153.62 m2 g−1) providing the favorable electronic and lithium ion transport by increasing the contact area with the electrolyte, as well as the presence of metal Co thorns. The present study offers a strategy for the rational synthesis of promising anodes with hierarchical structures for superior lithium storage.