The challenges for rechargeable lithium‐oxygen batteries of low practical capacity and poor round‐trip efficiency urgently demand effective cathode materials to overcome the limitations. However, the synergy between the multiple active materials is not well understood. Here, findings of the synergistic effect between electrospun zinc oxide (ZnO) nanofibers and graphene nanoribbons (GNRs) unzipped from carbon nanotubes (CNTs) as cathode materials in rechargeable lithium‐oxygen batteries are described. Furthermore, the overpotentials and discharge capacities are tuned by the surface defect states of ZnO nanofibers and Pt nanocrytals in GNRs. It is observed that the optimized zinc oxide nanofibers hybridized with GNRs achieved a high reversible capacity of 6300 mAh g‐1carbon and enhanced stable cyclability under specific 50% of full discharge capacities. This report demonstrates that the ZnO nanofibers with a high degree of defects and hydrophilicity of the surface may be a promising cathode component for rechargeable lithium‐oxygen batteries and the optimum synergy between ZnO nanofibers and GNRs can balance the discharge capacity and cycle life.

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Batteries for high-rate applications such as electric vehicles need to be efficient at mobilizing charges (both electrons and ions). To this end, choice of the conductive carbon in the electrode can make a significant difference in the performance of the electrode. In this work, graphene nanoribbons (GNRs) are explored as conductive pathways for a silicon-based anode. Water-based electrospinning is employed to directly deposit poly(vinyl alcohol) (PVA)−silicon−graphene nanoribbon composite fibers on a copper current collector. The size of the employed GNRs dictates their placement: either inside each fiber (small GNRs) or as a bridge between multiple fibers (large GNRs). Galvanostatic charge/discharge cycles reveal that fibers with GNRs have higher capacity and overall retention compared to those with corresponding precursor carbon nanotubes (CNTs). To further distinguish the effectiveness of GNRs as the conductive agent, samples with two GNRs and their parent CNTs were subject to rate-capability tests. Fibers with large GNR inclusions exhibit an excellent performance at fast rates (1400 mAh g −1 at 12.6 A g −1 ). For both pairs, enhancement in the performance of GNRs over CNTs grows with increasing rates. Finally, a small amount of large GNRs (1 wt %) is blended with small GNRs in the fibers to create synergy between intra-and interconductivity provided by small and large GNRs, respectively. The resulting fiber mat exhibits the same capacity as that of only small GNRs, even at a current rate that is 4 times higher (300 mAh g −1 at 21 A g −1 ).

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