Hierarchical High‐Porosity Graphene Oxide‐Porous Carbon/Sulfur Composite with Sodium Chloride as Temporary Space Holders for High‐Performance Lithium‐Sulfur Batteries

Abstract

AbstractThe ultrahigh theoretical specific capacity and energy density of lithium‐sulfur batteries have attracted extensive research, but the main issues including the insulating nature of sulfur, large volumetric expansion during discharging, and shuttle effect of polysulfides still need to be solved. Herein, a hierarchical high‐porosity graphene oxide‐porous carbon/sulfur (GO‐PC/S) composite cathode is designed and fabricated. In this work, sodium chloride was used as temporary space holders to create a hierarchical porous structure for accelerating the transmission of Li+, accommodating the volumetric expansion, and enlarging the specific surface area (342.623 m2 g−1) up to eight times. Owing to the abundant oxygen‐containing functional groups of GO, sulfur and polysulfides can be effectively immobilized and the conductivity is enhanced by porous carbon. The Li−S battery exhibits outstanding kinetic performance and rate capability (618.3 mAh g−1 at 2 C) as well as excellent cycling performance over 300 cycles.