Synergic adsorption and catalytic conversion of polysulfides based on polar Mo2C and pyridinic N for the enhanced electrochemical performance of Li–S batteries

As a most promising potential next-generation energy storage system , lithium-sulfur batteries (Li–S batteries) received great attention in recent years. However, how to effectively prevent the shuttling effect and accelerate the redox reaction kinetics of polysulfides are still a challenge. Herein, a strategy of using the soft template as a pore-forming agent was proposed to prepare Mo 2 C/nitrogen-doped carbon hollow microflowers (marked as H–Mo 2 C/NC MFs), which was used as an efficient absorbent and electrocatalyst of polysulfides for Li–S batteries. Due to the physical limitations of assembling the special nanosheet into a hollow carbon matrix in the shape of a microflower, the H–Mo 2 C/NC MFs can be used as an appropriate S loading substrate. With the synergistic chemisorption from pyridine N sites and high content polar Mo 2 C nanoparticles , the as-prepared H–Mo 2 C/NC MFs can provide enhancing adsorption and catalytic conversion for polysulfides. As a result, the H–Mo 2 C/NC/S MFs-based cathode provides a high initial discharge capacity of 1104.8mAh/g at 0.2C. Even at the high rate of 1.0C, the initial capacity of 705.2mAh/g still shows good electrochemical performance, and in 1000 cycles, the average capacity decay rate is only 0.016%, with supercycle stability. This article provided a new strategy for a novel viewpoint for the reasonable design of conductive and polar materials for efficient and durable Li–S batteries.