Room-temperature sodium-sulfur (RT Na-S) batteries have aroused extensive interest from researchers owing to the high theoretical volumetric energy density, nontoxicity and low-cost. However, poor conductivity of sulfur and high solubility of polysulfides in electrolyte are two major challenges for the practical application of the RT Na-S batteries. Herein, we report a three dimensional self-supported structure with Vanadium carbide (VC) nanoparticles embedded in carbon nanofibers for RT Na-S batteries. Finally, the VC-CNFs@S electrode displays a reversible capacity of 379 mAh g⁻¹ after 2000 cycles at 0.5C with a high capacity retention of 96.2%. Such outstanding electrochemical property is ascribed to the “confining – trapping – catalyzing” effect of VC-CNFs structure.

由于理论体积能量密度高，无毒且成本低廉，室温钠硫（RT Na-S）电池引起了研究人员的广泛兴趣。然而，硫的电导率差和多硫化物在电解质中的高溶解度是RT Na-S电池实际应用的两个主要挑战。在本文中，我们报道了RT Na-S电池的碳纳米纤维中嵌入了碳化钒（VC）纳米粒子的三维自支撑结构。最后，VC-CNFs @ S电极在0.5C下经过2000次循环后显示出379 mAh g ^-1的可逆容量，具有96.2％的高容量保持率。如此出色的电化学性能归因于VC-CNFs结构的“限制-捕获-催化”作用。