Defect engineering on carbon black for accelerated Li-S chemistry

Rationally designing sulfur hosts with the functions of confining lithium polysulfides (LiPSs) and promoting sulfur reaction kinetics is critically important to the real implementation of lithium-sulfur (Li-S) batteries. Herein, the defect-rich carbon black (CB) as sulfur host was successfully constructed through a rationally regulated defect engineering. Thus-obtained defect-rich CB can act as an active electrocatalyst to enable the sulfur redox reaction kinetics, which could be regarded as effective inhibitor to alleviate the LiPS shuttle. As expected, the cathode consisting of sulfur and defect-rich CB presents a high rate capacity of 783.8 mA·h·g−1 at 4 C and a low capacity decay of only 0.07% per cycle at 2 C over 500 cycles, showing favorable electrochemical performances. The strategy in this investigation paves a promising way to the design of active electrocatalysts for realizing commercially viable Li-S batteries.