通过协同的表面涂层和兴奋剂,调节离子层氧化物阴极的氧气释放
Xue-Li Zhang1, Zhi-Xiong Huang2, Yan-Ning Liu1
1Faculty of Chemistry, Northeast Normal University, Changchun, Jilin 130024, PR China.
Journal of colloid and interface science
|July 13, 2023
概括
这项研究通过使用氧化 (CeO2) 表面修饰和兴奋剂来增强离子电池阴极材料. 这一策略抑制了氧气损失,改善了结构稳定性和电化学性能,以获得更好的电池.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 计算化学计算化学
背景情况:
- 层层的过渡金属氧化物是离子电池的有希望的阴极材料.
- 循环过程中的氧气损失导致这些材料的结构降解和容量衰减.
- 尼奥债券被确定为一个关键的弱点,导致结构性失败.
研究的目的:
- 为了提高离子电池的分层过渡金属氧化物的结构稳定性和电化学性能.
- 调查氧化 (CeO2) 表面修饰和兴奋剂在减轻氧气损失中的作用.
- 了解CeO2增强氧氧还氧反应可逆性的机制.
主要方法:
- 密度函数理论 (DFT) 的计算被用来分析债券强度和反应机制.
- 对Na0.67Mn0.7Ni0.2Co0.1O2 (MNC) 阴极材料进行了协同的表面CeO2修饰和痕迹Ce兴奋剂.
- 进行了电化学循环测试,以评估容量保留和稳定性.
主要成果:
- DFT的计算证实了Ni-O债券是最弱的,容易在充电时释放过多的能量.
- 证明CeO2修饰和兴奋剂可以刺激氧氧还原并提高其可逆性.
- 与未经修改的版本 (33.84%) 相比,经过修改的MNC阴极表现出显著增强的容量保留 (77.37%在200个周期内).
结论:
- 协同的表面CeO2涂层和兴奋剂通过促进从CeO2到MNC的电子转移来有效地抑制氧气损失.
- 这种方法可以防止Ni-O键破坏,并在离子电池循环过程中增强结构完整性.
- 该战略为开发用于离子电池的稳定和高性能阴极材料提供了一个有前途的途径.
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