2D层结构Bi到准1D结构NiBi3:结构尺寸缩小到优质的和离子储存
Guoping Liu1, Zhipeng Sun1, Xiaoyan Shi1
1School of Materials and Energy, Guangdong University of Technology, Guangzhou, 510006, China.
Advanced materials (Deerfield Beach, Fla.)
|August 7, 2023
概括
研究人员将2D石转化为准1DNiBi3用于离子和离子电池. 这种新的结构增强了反应动力学和稳定性,为高性能阳极提供了有前途的战略.
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:
- 层结构 (Bi) 是离子 (Na-ion) 和离子 (K-ion) 电池的有前途的阳极材料,因为它具有高体积容量和适当的氧化还原潜力.
- 然而,Bi阳极的实际应用受到循环过程中大量体积膨胀和缓慢的离子扩散动力学的阻碍,导致循环稳定性和速率能力差.
研究的目的:
- 为离子和K离子电池开发一种新型阳极材料,以提高循环稳定性和速率能力.
- 为了研究结构维度减小对木基阳极的电化学性能的影响.
- 阐明在新阳极材料的循环过程中反应机制和形态演变.
主要方法:
- 采用了结构维度减少策略,将2D层结构的Bi转换为准1D结构的NiBi3.
- 电化学性能通过静电循环对Na-ion和K-ion存储进行评估.
- 使用in-situ/ex-situ表征技术研究反应机制和循环驱动形态重建.
主要成果:
- 与2D Bi.相比,准1D NiBi3金属间化合物表现出增强的反应动力学和可逆性.
- 对于离子存储,NiBi3在 15,000 个循环后提供了 94.1% (332 mAh g-1) 的优异容量保留.
- 对于K离子储存,NiBi3显示出高初始的库伦比效率93.4%,提高容量保留.
结论:
- 从2D Bi降低到准1D NiBi3的结构维度是提高Na-ion和K-ion电池阳极性能的有效策略.
- 由此产生的NiBi3材料提供了卓越的循环稳定性,高速率能力和改进的离子扩散通路.
- 这项工作为设计高性能电池阳极提供了新的途径,通过结构操纵和理解循环过程中形态重建.
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