Nitrogen and oxygen dual-doped porous carbon derived from natural ficus microcarpas as host for high performance lithium-sulfur batteries

Abstract A novel nitrogen and oxygen dual-doped porous carbon (NOPC) has been prepared from the aerial roots of ficus microcarpas through a facile carbonization and activation approach using KOH as the chemical activating agent. The obtained NOPC has very large specific surface area of 2294 m2 g−1 and high pore volume of 1.15 cm3 g−1. Thanks to the high specific surface area and the doping of nitrogen and oxygen, the prepared NOPC/S cathode with a sulfur content of 55.9% shows a high initial discharge capacity of 1338 mA h g−1 at 0.1 C and retains 1047 mA h g-1 after 200 cycles. What is more, the NOPC/S-62.9% cathode also remains high capacity of 1036 mA h g-1 and the coulomb efficiency remains 98.3% after 200 cycles. Taking into account of the low cost, green and sustainable development, NOPC/S composites show good prospects in the application of lithium-sulfur batteries.