Nitrogen, Oxygen and Cobalt multiple-doped graphitized mesoporous carbon as a cost-effective carbon host with high sulfur content for lithium-sulfur batteries

The development of facile, inexpensive and large-scale methods to prepare carbon scaffolds with high sulfur content is crucial to the practical applications of Li-S Battery. Herein, Nitrogen, Oxygen and Cobalt multiple-doped graphitized mesoporous carbon sulfur composites (N-O-Co-C/S) with high sulfur content (90%) are developed via inexpensive carbonization methods. The composites exhibit superior performance with a capacity of 610 mAh g−1 at a current of 0.5 C after 200 cycles and 302 mAh g−1 at a current of 2 C after 1400 cycles. The superior performance of N-O-Co-C/S composites can be attributed to the enhanced electrical conductivity and ionic conductivity of Co-N-O-C/S composites, which can be supported by electrochemical impedance spectroscopy measurement. The polysulfide-trapping was mainly attributed to the strong O-S, N-S and Co-S interactions, thus improving the e electrochemical performance.