Rational design of a cobalt sulfide nanoparticle-embedded flexible carbon nanofiber membrane electrocatalyst for advanced lithium–sulfur batteries

Abstract

Both the sluggish redox kinetics and severe polysulfide shuttling behavior hinders the commercialization of lithium–sulfur (Li–S) battery. To solve these obstacles, we design a cobalt sulfide nanoparticle-embedded flexible carbon nanofiber membrane (denoted as CoS2@NCF) as sulfiphilic functional interlayer materials. The hierarchically porous structure of carbon nanofiber is conducive to immobilizing sulfur species and facilitating lithium-ion penetration. Moreover, electrocatalytic CoS2 nanoparticles can significantly enhance the catalytic effect, achieving favorable adsorption-diffusion-conversion interface of polysulfide. Combined with these synergistic features, the assembled Li–S cell with CoS2@NCF interlayer exhibited a great discharge capacity of 950.9 mAh g−1 with prolonged cycle lifespan at 1 C (maintained 648.1 mAh g−1 over 500 cycles). This multifunctional interlayer material used in this contribution provides an advanced route for developing high-energy-density Li–S battery.

Watermelon Flesh‐Like Ni3S2@C Composite Separator with Polysulfide Shuttle Inhibition for High‐Performance Lithium‐Sulfur Batteries

“…The“adsorption‐diffusion‐conversion” mechanism has already been proposed. [ 47–51 ] Polar materials have high adsorption and strong catalytic effect on LiPSs, but most of these components have poor electrical conductivity. Thus, a synergistic strategy of compounding polar materials with carbon materials is proposed.…”

Ni-NiS Heterojunction Composite-Coated Separator for High-Performance Lithium Sulfur Battery

“…Lithium-sulfur batteries have attracted great attention in the next generation of electrochemical energy storage systems due to their high theoretical specific capacity (1675 mAh/g) and high theoretical energy density (2600 Wh/kg), low cost, and environmental friendliness [1-3]. However, the shuttle effect and slow REDOX kinetics of lithium polysulfides (LiPSs) lead to low sulfur utilization rate, short cycle life, poor rate performance, which hinder the application of Li-sulfur batteries [4][5][6][7][8]. It is found that transition metals and metal compounds can effectively promote the conversion of soluble long-chain polylithium sulfide to short-chain lithium sulfide, improve their reaction kinetics, and effectively inhibit the shuttle effect, so as to achieve good long-cycle performance and rate performance more effectively [9][10][11][12][13][14][15][16][17].…”