多级孔结构MoO2纤维/S复合正极材料的合成及电化学性能研究

项目名称： 多级孔结构MoO2纤维/S复合正极材料的合成及电化学性能研究

项目编号： No.51504101

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 矿业工程

项目作者： 姚山山

作者单位： 江苏大学

项目金额： 20万元

中文摘要： 实现硫正极的高容量与高稳定性是锂硫电池应用化的关键。添加纳米氧化物可有效提高硫正极利用率及稳定性，但低导电率制约了其在锂硫电池中的应用。本项目提出电纺丝技术制备导电MoO2微/纳纤维，通过熔融浸渍法合成多级孔结构MoO2纤维/硫复合正极材料。设计具有吸附聚硫锂及催化锂/硫氧化还原反应能力的导电MoO2纤维，利用其多级孔结构、电催化活性和良好的导电性，提高硫利用率与正极电子电导，进而提高锂硫电池循环性能。调控电纺丝制备过程参数，探索多级孔结构MoO2纤维/硫复合正极材料界面结构及形成机理，阐明多级孔结构MoO2纤维催化锂/硫氧化还原反应机制，研究电极体系多相界面反应过程动力学，揭示MoO2纤维/硫复合正极材料充放电过程中电化学行为。本项目的实施为制备高效、稳定、长寿命的新型锂硫电池正极材料提供新思路和新方法，对构筑具有优良循环性能的高比能量锂硫二次电池体系具有重要的科学意义和潜在的应用前景。

中文关键词： 导电氧化物纤维；复合电极；多级孔结构；催化锂/硫氧化还原反应机制；电纺丝

英文摘要： The high capacity and high stability of sulfur cathodes are the key to the application of lithium sulfur batteries. Nano oxides as additives can effectively improve the utilization and stability of the sulfur electrode, but the lower conductivity of the oxides restrict its application in lithium sulfur batteries. In this project, the conductive of MoO2 micro/nano fibers are prepared by electrospinning and the hierarchical porous structure of MoO2 fibers/sulufr composite cathode are prepared by heating sulfur. The conductive oxide of MoO2 is designed, which have adsorption polysulfides and catalytic lithium/sulfur redox reactions by hierarchical porous structure, electrocatalytic activity and high conductive. MoO2 as additives could improve the sulfur cathode electron conductivity and utilization, which are expected to improve the cycle performance of the lithium sulfur batteries. It is necessary to study on the parameters of preparation material. The formation mechanism of the interface structure in the composite cathode will be discussed. The catalytic lithium/sulfur redox reactions by hierarchical porous structure of MoO2 fibers will be explored. The multpihase interface reaction kinetics will be discussed. The electrochemical performance of MoO2 fibers/sulfur composite cathode will be researched in charging and discharging process. The project advances a new idea and method to prepare cathode materials for lithium sulfur batteries with high efficiency, stable and excellent cycling performance, and build a high energy density with excellent cycle performance lithium sulfur secondary batteries system, and have important academic significance and potential application prospect.

英文关键词： Conductive oxides fibers;Composite electrode;Hierarchical porous structure;Catalytic mechanism of lithium/sulfur redox;Electrospinning