振动解析的RIXS揭示了氧氧还原活性离子电池阴极中的OH组形成
Moritz Hirsbrunner1, Anastasiia Mikheenkova2, Pontus Törnblom1
1Condensed Matter Physics of Energy Materials, Division of X-ray Photon Science, Department of Physics and Astronomy, Uppsala University, Box 516, 751 20 Uppsala, Sweden. laurent.duda@physics.uu.se.
Physical chemistry chemical physics : PCCP
|July 8, 2024
概括
振动分辨率共振无弹性X射线散射 (VR-RIXS) 检测离子电池阴极中的基组. 这种技术为电池材料中的氧气反应提供了新的见解.
科学领域:
- 材料科学 材料科学 材料科学
- 化学 化学 化学
- 物理 物理学 物理
背景情况:
- 离子电池对于电动汽车和下一代能源存储至关重要.
- 了解阴极材料中的氧氧还原活性是提高电池性能的关键.
- 振动解析共振无弹性X射线散射 (VR-RIXS) 是一种新兴的材料表征技术.
研究的目的:
- 在OK边缘使用VR-RIXS识别离子电池阴极中的嵌入分子.
- 研究氧氧还原活性阴极材料中基 (OH) 基的存在和行为.
- 探索VR-RIXS的潜力,以了解电池材料中的氧气反应.
主要方法:
- 在OK边缘使用振动分辨率共振无弹性X射线散射 (VR-RIXS).
- 分析了两个氧氧还原活性阴极材料:LiNi$_{0.90}$Co$_{0.05}$Al$_{0.05}$O$_{2}$ (NCA) 和Li$_{1.2}$Ni$_{0.13}$Co$_{0.13}$Mn$_{0.54}$O$_{2}$ (LRNMC). 这两种材料均具有氧氧还原活性.
- 研究OH组的形成,积累和RIXS信号特征.
主要成果:
- 检测到一个新的VR-RIXS签名在533 eV以上,归因于离子电池阴极中的OH组.
- 在初始循环期间,在LRNMC中观察到OH信号强度和电荷状态之间的相关性,且不完全可逆.
- 在长期循环NCA中发现保留的OH组RIXS信号强度.
结论:
- VR-RIXS是一种强大的工具,用于识别电池阴极材料中的OH组.
- 在活性阴极材料中形成和积聚OH组,影响电池性能.
- VR-RIXS为获得关于电池材料中氧气反应的基本见解提供了一条新的途径.
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