In situ sulfur loading in graphene-like nano-cell by template-free method for Li-S batteries

Carbon nanomaterials with 3D structures as sulfur hosts have been widely developed in lithium-sulfur batteries because of their high specific surface area, high conductivity and structural stability. However, sulfur, loaded by melting-diffusion method, is usually attached to the outside surface of carbon host, resulting in weak adsorption to expose polysulfide. Herein, we report a template-free method for synthesizing graphene-like nano-cell (GLC) with high in situ sulfur loading (S@GLC). The GLC is expected to provide physical adsorption by enclosed graphene cell architecture and chemical adsorption by pyridinic N-doping and oxygen functional group. With these merits, the S@GLC cathode owned high sulfur content (72%) and also, it exhibited a reversible specific capacity of 1253 mA h g^-1 at 0.2C, excellent rate performance, and long cycling stability (502 mA h g^-1 after 400 cycles at 1C).