通过TbF3处理实现超稳定的同自由丰富氧化物
Zhaojin Li1, Wei Song1, Di Zhang1
1Hebei Key Laboratory of Flexible Functional Materials, School of Materials Science and Engineering, Hebei University of Science and Technology, Hebei 050018, China.
ACS applied materials & interfaces
|May 2, 2024
概括
用F和Tb对Co-free富的Mn基阴极材料进行双重注,提高了离子电池的结构稳定性和容量保留,在300个循环后达到95.1%的保留.
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
- 储能 储能 储能 储能 储能 储能
背景情况:
- 基于Co-free Li-rich Mn的正极材料 (Co-free LRMOs) 由于成本,容量和环保性,对下一代离子电池具有前景.
- 无LRMO的高压运行会导致氧气释放和结构降解等问题,由于缺乏而加剧.
- 开发稳定的无C0LRMO对于推进高性能能源存储至关重要.
研究的目的:
- 增强无C0LRMO的结构稳定性和循环寿命.
- 通过使用F和Tb兴奋剂来研究纳米级双重修饰的效应.
- 了解负责提高电化学性能的潜在机制.
主要方法:
- 简单的一步固相反应策略被用于纳米级的双重修饰.
- 无辅助LRMO被添加了 (F) 和 (Tb).
- 评估了电化学性能 (放电能力,循环保留) 和结构稳定性.
主要成果:
- 双重F和Tb兴奋剂导致了优异的结构稳定性,在300个循环后保留了95.1%的初始容量.
- 这种容量保留是以Ni/Mn为基础的丰富材料报告的最高值.
- 虽然利率表现没有显著改善,但稳定性大大提高.
结论:
- 用F和Tb进行纳米级的双剂有效地改善了无CowLRMOs的结构完整性和循环寿命.
- F兴奋剂增加氧气空缺和Ni3+度,而Tb兴奋剂抑制氧气释放并改善离子/电子运输.
- 这种双重修改策略为开发更安全,更耐用的离子电池的先进阴极材料提供了可行的途径.
相关概念视频
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