Na 3 V 2 (PO 4 ) 3 (denoted as NVP) has been considered as a promising cathode material for room temperature sodium ion batteries. Nevertheless, NVP suffers from poor rate capability resulting from the low electronic conductivity. Here, the feasibility to approach high rate capability by designing carbon-coated NVP nanoparticles confi ned into highly ordered mesoporous carbon CMK-3 matrix (NVP@C@CMK-3) is reported. The NVP@C@CMK-3 is prepared by a simple nanocasting technique. The electrode exhibits superior rate capability and ultralong cyclability (78 mA h g −1 at 5 C after 2000 cycles) compared to carbon-coated NVP and pure NVP cathode. The improved electrochemical performance is attributed to double carbon coating design that combines a variety of advantages: very short diffusion length of Na + /e − in NVP, easy access of electrolyte, and short transport path of Na + through carbon toward the NVP nanoparticle, high conductivity transport of electrons through the 3D interconnected channels of carbon host. The optimum design of the core-shell nanostructures with double carbon coating permits fast kinetics for both transported Na + ions and electrons, enabling high-power performance.

A flexible and free‐standing porous carbon nanofibers/selenium composite electrode (Se@PCNFs) is prepared by infiltrating Se into mesoporous carbon nanofibers (PCNFs). The porous carbon with optimized mesopores for accommodating Se can synergistically suppress the active material dissolution and provide mechanical stability needed for the film. The Se@PCNFs electrode exhibits exceptional electrochemical performance for both Li‐ion and Na‐ion storage. In the case of Li‐ion storage, it delivers a reversible capacity of 516 mAh g−1 after 900 cycles without any capacity loss at 0.5 A g−1. Se@PCNFs still delivers a reversible capacity of 306 mAh g−1 at 4 A g−1. While being used in Na‐Se batteries, the composite electrode maintains a reversible capacity of 520 mAh g−1 after 80 cycles at 0.05 A g−1 and a rate capability of 230 mAh g−1 at 1 A g−1. The high capacity, good cyclability, and rate capability are attributed to synergistic effects of the uniform distribution of Se in PCNFs and the 3D interconnected PCNFs framework, which could alleviate the shuttle reaction of polyselenides intermediates during cycling and maintain the perfect electrical conductivity throughout the electrode. By rational and delicate design, this type of self‐supported electrodes may hold great promise for the development of Li‐Se and Na‐Se batteries with high power and energy densities.

Free-standing and binder-free porous carbon nanofibers (P-CNFs) electrodes were prepared by pyrolysis of PAN-F127/DMF nanofibers via an electrospinning process as potential anodes for Na-ion batteries (NIB). The P-CNFs delivers a reversible capacity of 266 mA h g(-1) after 100 cycles at 0.2 C, corresponding to ~80% of the initial charge capacity. When cycled at a current density as high as 500 mA g(-1) (2 C), it still delivers a reversible capacity of ~140 mA h g(-1) after 1000 cycles. The improvement of electrochemical performance is attributed to the special design and microstructure of P-CNFs, which conferred a variety of advantages: hierarchical porous channels enabling short transport length for ions and electrons, 3D interconnected structure resulting in low contact resistances, good mechanical properties leading to the excellent morphology stability.

Flexible and free-standing sulphur/(PCNFs-CNT) composite (S@PCNFs-CNT) electrode was successfully prepared by infiltrating sulfur into microporous carbon nanofibers-carbon nanotube (PCNFs-CNT) composite. When used as a cathode material for Li-S batteries, the S@PCNFs-CNT exhibits much better cycle performance and rate performance compared to CNT-free S@PCNFs. It delivers a reversible capacity of 637 mA h g(-1) after 100 cycles at 50 mA g(-1) and a rate capability of 437 mA h g(-1) at 1 A g(-1). The improved electrochemical performance is attributed to synergistic effect of the 3D interconnected structure, the additive of CNT, and the uniform distribution of micropores (<2 nm) in the PCNFs-CNT matrix. Our results indicate the potential suitability of PCNFs-CNT for efficient, free-standing, and high-performance batteries.

A one-step synthesis procedure is developed to prepare flexible S Se @carbon nanofibers (CNFs) electrode by coheating S Se powder with electrospun polyacrylonitrile nanofiber papers at 600 °C. The obtained S Se @CNFs film can be used as cathode material for high-performance Li-S batteries and room temperature (RT) Na-S batteries directly. The superior lithium/sodium storage performance derives from its rational structure design, such as the chemical bonding between Se and S, the chemical bonding between S Se and CNFs matrix, and the 3D CNFs network. This easy one-step synthesis procedure provides a feasible route to prepare electrode materials for high-performance Li-S and RT Na-S batteries.

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Electrospinning has attracted tremendous attention in the design and preparation of 1D nanostructured electrode materials for lithium-ion batteries (LIBs) and sodium-ion batteries (NIBs), due to the versatility and facility. In this review, we present a comprehensive summary of the development of electrospun electrode nanomaterials for LIBs and NIBs, and a brief introduction about electrode materials beyond LIBs and NIBs. By summarizing various electrochemical active materials, this review focuses on the evolution in structures and the constitution of electrospun electrode materials. In detail, a variety of electrospun anode and cathode materials of LIBs and NIBs have been properly discussed, respectively. Finally, the current progress in the electrospun electrode materials is well reviewed and the development direction is also pointed out. We believe that in the nearly future, electrospun electrode materials would be applied in commercial LIBs and promote the advance in NIBs. And we hope that this review could be helpful in the design and fabrication of electrospun hierarchical materials for other advanced energy-storage devices.