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Carbonaceous anode materials are commonly utilized in the energy storage systems, while their unsatisfied electrochemical performances hardly meet the increasing requirements for advanced anode materials. Here, activated amorphous carbon (AAC) is synthesized by carbonizing renewable camellia pollen grains with naturally hierarchical structure, which not only maintains abundant micro- and mesopores with surprising specific surface area (660 m2 g−1), but also enlarges the interlayer spacing from 0.352 to 0.4 nm, effectively facilitating ions transport, intercalation, and adsorption. Benefiting from such unique characteristic, AAC exhibits 691.7 mAh g−1 after 1200 cycles at 2 A g−1, and achieves 459.7, 335.4, 288.7, 251.7, and 213.5 mAh g−1 at 0.1, 0.5, 1, 2, 5 A g−1 in rate response for lithium-ion batteries (LIBs). Additionally, reversible capacities of 324.8, 321.6, 312.1, 298.9, 282.3, 272.4 mAh g−1 at various rates of 0.1, 0.2, 0.5, 1, 2, 5 A g−1 are preserved for sodium-ion batteries (SIBs). The results reveal that the AAC anode derived from camellia pollen grains can display excellent cyclic life and superior rate performances, endowing the infinite potential to extend its applications in LIBs and SIBs.

To overcome intrinsic low electronic conductance, delicately designed fiber-shape Na3V2(PO4)2F3@N-doped carbon composites (NVPF@C) have been prepared for boosting Na-storage performance. This distinctive interlinked three-dimensional network structure can effectively facilitate electron/Na-ion transportation by decreasing the NVPF particle size to shorten the ionic diffusion paths and introducing a conducting N-doping carbon scaffold to improve electronic conductivity. Benefiting from the favorable structural design and fascinating reaction kinetics, the modified NVPF@C material demonstrates superior sodium-storage performance with 109.5 mAh g–1 high reversible capacity at a moderate current of 0.1 C, excellent rate tolerance of 78.9 mAh g–1 at a high rate of 30 C, and gratifying long-term cyclability (87.8% capacity retention after 1000 cycles at 20 C; 83.4% capacity retention after 1500 round trips at a ultrahigh rate of 50 C). The fascinating electrochemical performance remains stable when NVPF@C was examined as the cathode material for a full cell, suggesting the fiber-shape NVPF@C as one of the most promising applicable materials for sodium-ion batteries. Moreover, the approach of the three-dimensional conductive network by electrospinning is proposed as a strategy of efficiency and promising prospect to enhance the electrochemical property of other materials for sodium-ion batteries.

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