1. Parisa Shabani Nezhad, Prof. Junjie Niu*
Core-Shell Structure of Sulfur-Polypyrrole for Lithium-Sulfur Batteries
Parisa Shabani Nezhad, Prof. Junjie Niu*

2. Li-S vs. other cell chemistries

3. Challenges

4. Experimental

5. Result & discussion
(a)TEM images of the S-polymer composite (b)Magnified image of a single sulfur−polymer core−shell particle (c)the corresponding EDX elemental mapping (d)EDX spectrum of composite.

6. Conclusion
The uniform and flexible PPy layer helps to encapsulate and confine the sulfur/polysulfides physically inside the core–shell structure, thus alleviating the volume expansion of sulfur and polysulfide effects during the cycling.
With PPy as a coating layer, the aggregation and growth of sulfur particles was also obviously avoided, which results in faster ion transfer.
Moreover, PPy as a conductive polymer can partly enhance the electrical conductivity of sulfur particles.

7. References
1.Xie et al, “Facile large-scale synthesis of core–shell structured composite and its application in lithium–sulfur batteries with high energy density”, Applied Energy 175 (2016), Zhou et al, “Yolk−Shell Structure of Polyaniline-Coated Sulfur for Lithium−Sulfur Batteries”, J. Am. Chem. Soc 135 (2013), 135 (44), Ni et al, “Core–Shell Structure and Interaction Mechanism of γ-MnO2 Coated Sulfur for Improved Lithium-Sulfur Batteries”, Small 13 (2017). 4.Niu et al, “Scalable synthesis of a sulfur nanosponge cathode for a lithium–sulfur battery with improved cyclability”, J. Mater. Chem. A (2014).