Preparation and Electrochemical Performance of Zn₂VO₄/N-CNFs Free-Standing Composite Interlayer by Electrospinning Technology

Zn, V bimetallic compound-carbon nanofibers free-standing interlayer (Zn₂VO₄/N-CNFs) with 3D mesh structure was designed for lithium sulfur (Li-S) batteries by electrospinning technology. The results show that the pyridine nitrogen and pyrrole nitrogen can strongly interact with lithium-ion, Zn₂VO₄ has a strong adsorption and catalytic effect on lithium polysulfide. The multi-layer carbon nanofiber network can also provide long-range electron conduction paths while capturing polysulfides, which can promote electron transfer and store electrolyte at the same time, providing the space for electrochemical reaction. The Zn₂VO₄/N-CNFs interlayer can play the bifunctional role of adsorbing and facilitating the transformation of lithium polysulfide. The battery with Zn₂VO₄/N-CNFs interlayer can deliver an initial discharge capacity of 796.1 mAh·g^-1 at 0.2 C, and keep at 727.2 mAh·g^-1 after 100 cycles with the capacity retention rate of 91.3%.In addition, the battery delivers an initial capacity of 593.4 mAh·g ^-1 at 1.0 C, and retains at 353.3 mAh·g ^-1 after 1000 cycles with corresponding capacity attenuation of 0.0024% per cycle.