锂空气电池中尖晶石催化材料电子结构与性能的软X射线光谱学研究

项目名称： 锂空气电池中尖晶石催化材料电子结构与性能的软X射线光谱学研究

项目编号： No.21473235

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 分析化学

项目作者： 刘啸嵩

作者单位： 中国科学院上海微系统与信息技术研究所

项目金额： 92万元

中文摘要： 提高氧还原/氧析出反应效率的催化剂是影响二次锂空气电池性能的一个关键因素，而选择、优化、设计催化材料的前提是从电子结构等微观机理层面理解其催化机制。目前，相比于材料合成方面的快速发展，针对决定材料性能的关键电子能级进行直接研究的实验手段仍显匮乏。本项目拟发挥软X射线光谱学在电子结构测量方面的独特优势，通过研究尖晶石纳米晶体MxMn3-xO4这一可应用于二次锂空气电池中氧还原/氧析出反应的催化剂，从电子结构的角度寻找影响材料催化性能的物理根源。在此基础上，通过发展原位反应装置，在锂空气电池运行条件下，实时考察电化学反应过程中材料电子结构的精细变化，以及不同反应阶段的生成产物。这项研究将有助于理解锂空气电池在充放电过程中的反应机理和尖晶石材料的催化机制等关键科学问题，从而为加速锂空气电池的研究和应用奠定科学技术基础。

中文关键词： 锂空气电池；电催化剂；电子结构；金属氧化物

英文摘要： The efficient electrocatalysts that overcome the sluggish kinetics of the oxygen electrochemical reaction is one of the key factors to improve the performance of rechargeable Li-air battery. To choose, optimize，and rationally design the electrocatalysts, it is a prerequisite to have insights into the microscopic mechanisms of the catalytic reactions, in particular from the point of view of the electronic structure. Compared with the rapid progress in material synthesis, we still need to develop novel experimental techiques with the capability to directly detect the key electronic states that determine the properites of materials. By taking the advantage of soft X-ray spectroscopy on probing the electronic structure, we here propose to investigate the spinel nanocrystals MxMn3-xO4, which are electrocatalysts for oxygen reduction reaction (ORR)/oxygen evolution reaction (OER) in Li-air battery, to understand the underlying physical origin of the catalytic properties. Furthermore, by developing the in-situ instruments, we will be able to achieve the in-situ and operando X-ray spectroscopic measurement to gain the insights on the detailed variation of electronic structures of catalysts, and distinguish the reaction products at different cycling stages. It will help us to have better understanding on the mechanisms of the electrochemical reaction in Li-air battery, as well as the electrocatalytic properties of the spinel nanocrystals. Eventually, it is possible to expedite the research and development of Li-air battery.

英文关键词： Li-Air Battery;Electrocatalysts;Electronic Structure;Metal Oxide