The surface modification of the separator for electrocatalyst in lithium-sulfur batteries

The introduction of electrocatalyst can promote redox kinetics to improve the performance of lithium-sulfur (Li-S) batteries. Currently, much attention has been paid to modify site and effectiveness of electrocatalysts. Herein, the commercial platinum carbon (Pt/C) material was investigated to modify the polypropylene separator from the cathode side (PP@Pt battery), which was compared with the cathode doped (C-S-Pt) and unmodified (PP) batteries. The results show that PP@Pt battery delivers superior cycle performance and cycling stability than other batteries, confirming that the catalytic effect of Pt/C layer on the separator precede that of cathode doping. This is attributed to that the highly dispersed Pt/C layer is in intimate contact with the sulfur electrode to provide sufficiently active sites, which not only enhances the electronic conductivity but also provides a desired reaction site.