可对多硫离子的扩散进行多级抑制的活化石墨烯基锂硫电池正极材料

项目名称： 可对多硫离子的扩散进行多级抑制的活化石墨烯基锂硫电池正极材料

项目编号： No.51202106

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 无机非金属材料学科

项目作者： 郑明波

作者单位： 扬州大学

项目金额： 24万元

中文摘要： 锂硫电池具有非常高的能量密度，有望大量应用于电动汽车等领域。如何抑制多硫离子的扩散，有效改善电池的循环性能与库仑效率，已成为应用中急需解决的关键问题之一。本项目将研究基于活化石墨烯的、可对多硫离子的扩散进行多级抑制的多重纳米结构复合材料体系。以三维纳米孔结构的颗粒状活化石墨烯为载体，制备活化石墨烯/硫复合体，接着在该复合体外表面负载介孔SiO2纳米粒子、包覆石墨烯纳米片，获得多重纳米结构复合材料。通过电化学测试分析，研究活化石墨烯纳米孔道的约束效应、介孔SiO2 的存储功能、石墨烯纳米片包裹层的限制作用，对多硫离子扩散的多级抑制特征。研发具有优异循环性能与库仑效率的锂硫电池正极材料，为其实际应用奠定坚实的实验基础。

中文关键词： 锂硫电池；活化石墨烯；纳米复合材料；多硫离子扩散；多级抑制

英文摘要： Lithium-sulphur battery has been expected to be applied to electric vehicles and other fields due to its very high energy density. In order to effectively improve the cycling performance and coulombic efficiency of the lithium-sulphur battery, the retardation of the diffusion of polysulphide ions during the reaction has become one of the research focuses in this field. In this project, we will develop an activated graphene-based nano-composite system, which can retard the diffusion of polysulphide ions at multilevel. Using the activated graphene with three-dimensional nanoporous structure as the support, the activated graphene/sulphur composite will be obtained. Then, mesoporous silica nanoparticles and graphene nanosheets will be coated on the outside surface of the the activated graphene/sulphur composite, and a multiple nano-composite system will be obtained. By the electrochemical test and analysis for the multiple nano-composite system, the restriction effect of the nanopore in activated graphene for polysulphide ions, the reservoir function of mesoporous silica for polysulphide ions, and the confinement effect of the graphene nanosheets coating for polysulphide ions will be studied systematically. The characteristic of the retardation at multilevel will also be studied. On the basis of the experimental wor

英文关键词： lithium–sulfur battery；activated graphene；nano-composite；diffusion of polysulphide ions；multilevel retardation