No abstract

Hierarchically porous carbon with inherently doped heteroatoms and the quantity of active material (sulfur) confined within this carbon matrix play a major role for the high performance of Li−S batteries. Herein, we discuss the influence of sulfur content and distribution onto the N and O co‐doped hierarchically porous biomass carbon matrix (PC) to achieve high specific capacitance and cycling stability. Sulfur encapsulated PC was prepared from an eco‐friendly source with a high surface area of 2065 m2 g−1 and a pore volume of 1.5 cm3 g−1. PC with 54, 68 & 73% of sulfur content (PCSCs) have been investigated as cathode materials for Li−S battery. PC with 54% sulfur displayed better performance with an initial discharge capacity of 1606 mA h g−1 and a cycling stability of 1269 mA h g−1 at 0.1C rate after 100 cycles due to better dispersion of sulfur in the porous architecture. The higher cycling stability of PCSC (54%) is due to the N and O co‐doped hierarchical porous carbon layers, enhancing the sulfur utilization ratio and mitigating the polysulfide shuttle during the cycling process.

No abstract

Here we report a novel multiwall carbon nanotube/sulphur/polyindole (MWCNT/S/PIN) nanocomposite as a cathode material for lithium–sulphur (Li–S) batteries to alleviate capacity decay.

Lithium−sulfur batteries (LSBs) received worldwide attention because of its high theoretical capacity of sulfur, 1675 mA h g −1 . However, the low electrical conductivity of sulfur, dissolution of polysulfides (PS) in the electrolyte, and PS shuttle toward the Li anode restricted its reach to the market. In this paper, we present a porous carbon material with multifunctionalities derived from honeycomb (HC) used as a conductive host for sulfur for the first time. Honeycomb derived carbon−sulfur composite with 80% of sulfur [HCS (80%)] gives a high reversible capacity of 1101 mA h g −1 at the 0.1 C rate after 200 cycles with 82% capacity retention. The coating of HC onto the cathode film [HCS (80%)] yielded 92% capacity retention, where sulfur is sandwiched between the two conductive hosts. Therefore, the HCS (80%) composite electrode with coating of HC [HCS (80%)−HC] exhibits good improvement in both cycling performance and rate capability compared to bare cathode HCS, even though the sulfur content of the HCS composite is as high as 80%. Thus, HCS (80%)−HC would be a potent combination for highperformance LSBs.