%0 Journal Article
%T 镍钴锰基正极材料表面结构演变机制研究<br>Study on the Evolution Mechanism of the Surface Structure of Nickel-Cobalt-Manganese-Based Cathode Materials
%A 郭亚晴
%A 楼平
%A 张炜鑫
%A 管敏渊
%A 曹元成
%J Journal of Advances in Physical Chemistry
%P 181-187
%@ 2168-6130
%D 2021
%I Hans Publishing
%R 10.12677/JAPC.2021.103017
%X <div style=\"text-align:justify;\">
	近年来，锂离子电池(LIBs)在日常生活中发挥着越来越重要的作用。在此，通过原子分析和球差校正扫描透射电子显微镜(STEM)以及电子能量损失谱(EELS)模拟分析，全面研究了层状过渡金属氧化物LiNi<sub>0.5</sub>Co<sub>0.2</sub>Mn<sub>0.3</sub>O<sub>2</sub> (NCM523)单晶颗粒的降解机制。材料表面附近的结构转变是包括催化、记忆和储能在内的广泛应用的功能机制的基础。在锂离子电池的层状氧化物阴极中，我们观察到岩盐相的转变是从近表层开始的，而不是从最表面开始。将原子水平的扫描透射电子显微镜成像与电子能量损失光谱相结合，我们发现重建的近表层，以层状和尖晶石状结构的离散斑块为特征，其中却存在大量的2价金属原子，我们的研究结果为层状阴极结构转变的原子尺度机制提供了基本的见解。<br />
In recent years, lithiumion batteries (LIBs) have been playing an increasingly important role in daily life. Here, the degradation mechanism of layered transition metal oxide LiNi<sub>0.5</sub>Co<sub>0.2</sub>Mn<sub>0.3</sub>O<sub>2</sub> (NCM523) single crystal particles was comprehensively investigated by atomic analysis and sphere-difference corrected scanning transmission electron microscopy (STEM) and electron energy loss spectroscopy (EELS) simulations. Structural transitions near the material surface are the basis for a wide range of functional mechanisms including catalysis, memory and energy storage. In the layered oxide cathode of lithiumion batteries, we observed that the rock salt phase transition starts near the surface rather than at the very surface. Combining scanning transmission electron microscopy imaging at the atomic level with electron energy loss spectroscopy, we find that the reconstructed near-surface layer, characterized by discrete patches of layered and spinel-like structures, nevertheless contains a large number of 2-valent metal atoms, and our results provide fundamental insights into the atomic-scale mechanism of the structural transition in layered cathodes.
</div>
%K 三元材料，失效机理，表面重构，球差电镜<br>Ternary Materials
%K Degradation Mechanism
%K Surface Reconstruction
%K Spherical Differential 
Electron Microscopy
%U http://www.hanspub.org/journal/PaperInformation.aspx?PaperID=44959