▎ 摘　　要

NOVELTY - Synthesizing graphene/sulfur composite, comprises (a) mixing graphene oxide with a hydrogen sulfide-releasing agent in a sealed vessel, (b) causing the hydrogen sulfide-releasing agent to release hydrogen sulfide, and (c) allowing the hydrogen sulfide to react with the graphene oxide at an elevated temperature and pressure to form the graphene/sulfur composite. USE - The method is useful for synthesizing graphene/sulfur composite which is directly used as a cathode material in a rechargeable lithium-sulfur battery (all claimed). ADVANTAGE - The method: significantly suppressed the diffusion of sulfur into electrolyte during charge/discharge cycles, due to the strong chemical bonding between sulfur and graphene; provides the graphene/sulfur composite, which has the sulfur loading of 5-80%, has an ultrahigh electronic conductivity of at least 9.5 S/cm-1, and provides the cathode with an initial charging capacity of at least 1200 mA hour/g at 0.2 C, a high discharging capacity of at least 700 mA hour/g at 2 C, and a retention rate of at least 67% after 70 cycles (claimed); completely utilizes hydrogen sulfide; and exhibits high scalability. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a graphene/sulfur composite prepared by the method, where the sulfur is homogeneously distributed on graphene with a strong chemical bonding interface.