LDH-derived Co0.5Ni0.5Te2 Dispersed in 3D Carbon Sheets as Separator Modifier to Enable Kinetics-Accelerated Lithium-Sulfur Batteries

Abstract

Lithium-sulfur battery is considered as a powerful candidate for the next generation of advanced energy storage systems relying on its high energy density and theoretical specific capacity. However, its practical commercial feasibility has been hampered by sluggish kinetics and severe shuttle effect. Hence, a novel hybrid that NiCo-LDH derived Co0.5Ni0.5Te2 nanoparticles grafted in 3D carbon sheets was rationally constructed by facile steps and acted as functional separator modifier for lithium sulfur battery. Therein, the 3D cross-linked conductive network structure is conductive to the continuous electron transfer. In addition, the well-dispersed Co0.5Ni0.5Te2 nanoparticles with hexahedral morphology offer ample sulfophilic surface to chemically anchor and catalyze the redox dynamic of sulfur species. It has been proved that the dynamic conversion of sulfur-involved reaction is effectively promoted and the utilizations of polysulfides are boosted. The related cells display attractive long cycling durability (784.8 mAh g-1 at 2C after 500 cycles) and excellent rate performance (699.5 mAh g-1 even at 7C). Furthermore, when sulfur loading is up to 6.89 mg cm-2, the areal capacity can still be maintained at 6.40 mAh cm-2 after 50 cycles at 0.2C. This work provides a promising strategy to design multifunctional separator modifier and promotes the exploration of metal tellurides to engineer advanced kinetics-accelerated lithium-sulfur batteries.