三维非金属掺杂MnO2基正极材料的精确调控及其锌离子电池性能的研究

Flexible zinc ion batteries are considering as one of the most promising candidates for the flexible energy storage devices due to their high specific capacity, non-toxic safety and no pollution. MnO2 with high discharge platform and theoretical capacity is one of the most promising electrode materials for flexible zinc ion batteries. The MnO2-based cathode materials used in zinc ion batteries have disadvantages such as low specific capacity and poor cycle stability. In this proposal, by controlling the crystal types and nonmetal doping, we will focus on the design of MnO2-based electrodes to improve its conductivity, the ion diffusivity and stability, as well as the high power capacity and durability of the ZIBs. By using the characterization methods of structures and constitutes, together with electrochemical methods, we will also explore systematically the relationships between preparative factors of electrodes and their electrochemical behavior, and the mechanism of the characteristic property and zinc ion battery activities. Based on the synthesized nonmetal doped MnO2 cathodes and Zn anodes, flexible zinc ion battery devices will be assembled, and the effects of non-metal doping conditions and states on battery performance will also be analyzed and summarized. We believe that this proposal can help us to provide an elementary new approaches and theoretical foundation for reasonably utilization of flexible zinc ion batteries.

柔性锌离子电池由于具有高比容量、无毒安全、无污染等特点，是目前柔性储能器件研究领域的重点和热点之一。具有较高放电平台和理论容量的MnO2是目前柔性锌离子电池最有前景的正极材料之一。但它存在导电性和循环稳定性较差的问题。本项目拟通过控制MnO2晶体构型和掺杂非金属元素来改善其导电性、离子扩散能力和结构稳定性等性质，以期实现高容量、长寿命的MnO2基正极材料的可控制备；利用结构、成分表征方法和电化学检测手段，探讨电极的晶体构型和形貌结构对于电极电化学行为的影响，明确其结构和性能调控机理。基于上述非金属掺杂的MnO2正极材料和Zn负极材料组装柔性锌离子电池器件，分析总结非金属掺杂条件与状态对电池性能的影响；为高导电性电极材料以及高性能柔性锌离子电池的设计和制备提供新的参考和实验依据。

本项目拟通过非金属掺杂和结构控制的方式制备得到具有高导电性、离子扩散能力和结构稳定性的三维NE-MnO2电极材料。项目执行过程中，本课题组探究了不同制备条件下MnO2结构和形貌的变化规律；研究了N、P掺杂三维NE-MnO2电极材料的制备技术；利用XRD、XPS、SEM、TEM等表征手段系统分析了三维NE-MnO2材料的形貌、晶体结构、掺杂非金属元素等因素对于电极材料的导电性、能量密度、功率密度和循环性能等电化学性能的影响。以富含氨基和羟基、低成本、天然大分子壳聚糖为前驱体，原位制备具有可控缺陷的N、O双掺杂碳基阴极材料；探究了碳材料表面N、O基团和缺陷类型、数目对材料表面化学结构和材料孔径分布的影响；通过调控材料比表面积和中孔比例，提升了锌离子超级电容器中碳基材料的比容量和稳定性。利用非原位和原位测试技术，检测分析锌离子超级电容器等锌基储能器件充放电过程中碳基材料等电极材料结构的变化；研制出能量及功率密度高、实用性较强的锌离子电池、锌空气电池和锌离子超级电容器等锌基储能器件。