Preparation And Properties Of Electrode Materials Composed Of Grapheme And Metal Sulfides

Owing to its unique two-dimensional planar construction with a single-atom thickness, graphene displays an excellent physicochemical properties and has a great prospect of applications in sensors, catalysts, biology and energy storage. In view of the advantages of graphene, we have successfully prepared various graphene-based composites with different macroscopic and microscopic structures, also an in-depth discussion have been made on the preparations, characterizations and applications.The detailed research contents of this thesis are summarized as follows:(1) Preparation of two-dimensional graphene/molybdenum disulfide composite and its performances in lithium batteriesLithium-ion batteries (LIBs) are becoming more and more attractive, and the need for superior performances motivated us to develop new materials. Herein, we describe the scalable assembly of free-standing 2D graphene-MoS2 composite films consisting of nitrogen-doped graphene and ultrathin honey-comb-like MoS2 nanosheets. This unique structure not only improves the conductivity and the transmission of electrons and lithium ions,but also provides a suitable space to avoid the breakage of NG-MoS2 which caused by the expansion of MoS2 during discharge/charge. The NG-MoS2 composite exhibits a high capacity,outstanding cycling and rate performance.(2) Preparation of three-dimensional graphene/tin disulfide composite and its performances in lithium batteriesHere we describe a free-standing 3D graphene-SnS2 composite composed of graphene loaded with SnS2 nanosheets. Except the excellent electrical conductivity, it also benefits for the contact between graphene and SnS2, leading to a rapid ionic access to the active material. The graphene-SnS2 composite exhibits an excellent performance.