▎ 摘　　要

NOVELTY - Preparing spheroidal nitrogen-doped reduced graphene oxide material comprises (a) diluting 0.5-12 mg/ml graphene oxide aqueous solution by and ultrasonically processing for 4-16 hours, spray-drying to obtain spherical graphene oxide powder, adjusting the inlet temperature of spray drying to 120-180 degrees C, outlet temperature to 80-140 degrees C, flow rate of feed peristaltic pump to 200-1000 ml/hour, and pass frequency to 2-6 second/time, (b) grinding and mixing the spherical graphene oxide powder with a nitrogen source, heating at 600-1200 degrees C for 0.5-6 hours under an argon or nitrogen atmosphere to obtain a spherical nitrogen-doped reduced graphene oxide material, where the mass ratio of the nitrogen source to spheroidal graphene oxide powder is 10-1:1, and the nitrogen source is at least one of melamine, urea, and polyvinylpyrrolidone. USE - The material is useful as a cathode material for lithium sulfur battery (claimed). ADVANTAGE - The material: has good electrical conductivity and high folding, large specific surface area and multi-stage pore structure, has rich functional groups, and avoids the serious stacking of graphene and adverse effects, can combine with sulfur which is suitable for cathode material of the lithium sulfur battery, achieves uniform dispersion of the active material, increases the sulfur content, improves the conductivity of the electrode and reduces the shuttle effect, and improves the electrochemical performance of the sulfur cathode. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) use of spherical nitrogen-doped reduced graphene oxide material as a cathode material for lithium sulfur battery by combining the material with sulfur; and (2) use method of spheroidal nitrogen-doped reduced graphene oxide material comprising mixing the spherical nitrogen-doped reduced graphene oxide material and sulfur powder in a sealed kettle filled with argon or nitrogen, transferring to a muffle furnace, heating at 1-3 to 100-130 degrees C/minute for 1-4 hours, heating at 0.5-5 to 150-160 degrees C/minute for 12-24 hours, and heating at 220-300 degrees C for 1-6 hour at 1-10 degrees C/minute to obtain a spherical nitrogen-doped reduced graphene oxide composite sulfur material, where the mass ratio of the spherical nitrogen-doped reduced graphene oxide material to the sulfur powder is 1:1.5-10.