Spatial confinement of the cellular wall of yeast to the insertion of Co for enhanced electrochemical performance of Li-S batteries

Uniformly distributing Co crystalline particles within hierarchical pores of the microbial carbon stemmed from microorganisms is promising to improve a desirably electrochemical performance of Lithium-Sulfur (Li-S) batteries. Yeast as a representative microbial carbon, was used for making an exploration of spatial confinement of the cellular wall of yeast to the insertion of Co. On the basis of our previous paper, role of spatial confinement of the cellular wall of yeast to inserted Co was discussed, the difference of cobalt crystalline particles grown in the cellular wall and the cytoplasm was analyzed by high-resolution scanning electron microscopy. It showed that yeast cellular wall with compact structure could better keep fine cobalt particles from agglomeration and merging than yeast cytoplasm with loose structure. The as-prepared Co-YC-SDS-700/S electrode exhibited a higher reversible capacity of 1161.6 mAh g−1 as rate returned to 0.1 C and a better cycling life with a capacity fading rate of 0.099% per cycle at 0.2 C. The electrochemical reaction performance also further illustrated that the smaller and the more uniform distribution of the cobalt particles, the higher the utilization of sulfur, the better the cycle stability of the Li-S electrode.