3D N-doped graphene nanomesh foam for long cycle life lithium-sulfur battery

The 3D N-doped graphene nanomesh foam (3DNGF) has been synthesized as the Lithium-sulfur battery cathode material for the first time. A method of in situ doping nitrogen and meanwhile etching graphene layer is introduced. The BET result shows the 3DNGF has a large specific surface area more than traditional three-dimensional graphene. Transmission electron microscopy (TEM) observation and Raman spectra confirm the nanoholes on the graphene. The 3DNGF/S composite exhibits an initial discharge capacity of 1134 mAh g⁻¹ at 0.2C in the first cycle with the sulfur utilization of 67%. The electrode reserves a specific capacity of 578 mAh g⁻¹ after 500 cycles at 0.5C, with a capacity decay of 0.06% per cycle. Its specific capacity at 2C can still reach to 729 mAh g⁻¹, indicating the good rate performance.