高性能锂空气电池石墨烯层级介孔结构空气电极及其协同催化增强研究

The metal-air batteries, especially Lithium -air batteries, provides a new direction for developing a new generation of high-energy density storage devices. To choose a hierarchical mesoporous graphene structure as air cathode of Li-air battery, In this project, we will investigate the microscopic mechanisms of synergistically enhanced catalysis effect and disclose the modulation laws to control catalytic properties of graphene air cathode by defects and doping. In theory, we will explore the effect of defects and doping on electron transport, catalytic activity and other properties of hierarchical mesoporous graphene air cathode, propose the design ideas of the hierarchical graphene for the application in lithium-air battery, and to establish a universal physical model of catalytic enhancement for the hierarchical mesoporous graphene air cathode. In experiment, we will prepare a series of hierarchical mesoporous graphene structures as air cathode and propose an experimental scheme to synergistically improve the capacity, cycle life, and stability of air cathode for high-performance Li-air batteries. By researching on this project ,it will expect a breakthrough in the design, performance and micro regulation of the catalytic mechanism of new air cathode for metal-air battery, and builds the scientific and technical basis for the applications of the graphene materials in the high-performance ultra-thin electrochemical energy storage devices.

以锂空气电池为代表的金属空气电池为新一代高能量密度储能器件的研制提供了新的方向。本项目拟选用石墨烯层级介孔结构作为锂空气电池的空气电极，探索石墨烯层级介孔结构协同增强空气阴极催化性能的微观物理机理，研究缺陷和掺杂对石墨烯空气阴极催化性能的调控规律。理论上，探索缺陷与掺杂层级介孔结构对锂空气电池空气电极的电子传输、催化活性等性能的影响规律，提出锂空气电池石墨烯层级介孔结构电极设计方法，并建立起普适的石墨烯层级介孔结构空气电极催化增强物理模型。实验上,制备出系列可显著提高锂空气电池性能的石墨烯层级介孔结构空气电极，提出采用石墨烯层级介孔结构实现锂空气电池比容量、循环寿命及稳定性协同增强的实验方案。通过本项目研究，期望在金属空气电池新型空气阴极的设计、性能调控及微观催化机制上有所突破，并为石墨烯材料在高能量密度电化学储能器件上的应用奠定科学和技术基础。

锂空气电池具有超高的能量密度，为新一代高能量密度储能器件的研制提供了新的方向。以石墨烯为代表的层级介孔碳基结构在锂空气电池电极、超级电容器等储能器件中具有极大的应用潜力。本项目以层级介孔碳基结构为主要研究对象，通过掺杂、引入缺陷和复合等方式，采用实验和理论结合的研究方法，从电极结构设计、催化增强机制和性能调控三个方面深入细致系统的开展了研究工作。首先从电极结构和反应机理出发，提出了构建层级介孔碳基结构调控锂离子和氧气吸脱附及其扩散、电解液与电极接触面积、有效活性位点、放电产物过氧化锂的量和形貌及其形成与分解反应热动力学难易程度等协同催化增强电化学性能的思路。构建了一系列生物质层级介孔碳电极、层级介孔碳包覆“零应变”材料电极和自支撑层级介孔电极，结合第一性原理计算和实验观测阐明了层级介孔结构的协同催化增强机制，形成了基于层级介孔碳基结构协同催化增强的电极设计方案，为功能化电极的设计和发展及其在相关领域的应用提供了理论基础与实验指导。研究成果已在J.Phys.Chem.Lett.,J. Power Sources, J. Mater. Chem.A,Electrochimica Acta等国际期刊发表标注论文27篇，被国内外同行在Angewandte Chemie International Edition, Advanced Material, Advanced Energy Materials, Chemical Society Reviews和Nature子刊等期刊上他引近700次，授权国家发明专利3项。培养博士生2名，硕士毕业生8名。