Multisize CoS2 Particles Intercalated/Coated-Montmorillonite as Efficient Sulfur Host for High-Performance Lithium-Sulfur Batteries

The chemisorption and catalysis of lithium polysulfides (LiPSs) are effective strategies to suppress the shuttle effect in lithium-sulfur (Li-S) batteries. Herein, multisize CoS2 particles intercalated/coated-montmorillonite (MMT) as an efficient sulfur host is synthesized. As expected, the obtained S/CoS2@MMT cathode achieves an absorption-catalysis synergistic effect through the polar MMT aluminosilicate sheets and the well-dispersed nano-micron CoS2 particles. Furthermore, efficient interlamellar ion pathways and interconnected conductive network are constructed within the composite host due to the intercalation/coating of CoS2 in/on MMT. Therefore, the S/CoS2@MMT cathode achieves an outstanding rate performance up to 5C (similar to 548 mAh g(-1)) and a high cycling stability with low capacity decay of 0.063 and 0.067 % per cycle for 500 cycles at 1C and 2C, respectively. With a higher sulfur loading of 4.0 mg cm(-2), the cathode still delivers satisfactory rate and cycling performance. It shows that the CoS2@MMT host has great application prospects in Li-S batteries.